Search results

The cat (Felis catus), commonly referred to as the domestic cat or house cat, is a small domesticated carnivorous mammal. It is the only domesticated species...

Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes (/sɜːrˈpɛntiːz/). Like all other squamates, snakes are ectothermic, amniote...

Birds are a group of warm-blooded vertebrates constituting the class Aves (/ˈeɪviːz/), characterised by feathers, toothless beaked jaws, the laying of...

The garden strawberry (or simply strawberry; Fragaria × ananassa) is a widely grown hybrid species of the genus Fragaria, collectively known as the strawberries...

A flower, also known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). Flowers consist...

Monkey is a common name that may refer to most mammals of the infraorder Simiiformes, also known as the simians. Traditionally, all animals in the group...

Fellatio (also known as fellation, and in slang as blowjob, BJ, giving head, or sucking off) is an oral sex act involving a person stimulating the penis...

Butterflies are winged insects from the lepidopteran suborder Rhopalocera, characterized by large, often brightly coloured wings that often fold together...

Coronavirus disease 2019 (COVID-19) is a contagious disease caused by the coronavirus SARS-CoV-2. The first known case was identified in Wuhan, China,...

Spiders (order Araneae) are air-breathing arthropods that have eight limbs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude...

BDSM is a variety of often erotic practices or roleplaying involving bondage, discipline, dominance and submission, sadomasochism, and other related interpersonal...

Rabies is a viral disease that causes encephalitis in humans and other mammals. It was historically referred to as hydrophobia ("fear of water") due to...

Mollusca is the second-largest phylum of invertebrate animals, after Arthropoda; members are known as molluscs or mollusks (/ˈmɒləsks/). Around 76,000 extant...

Squirrels are members of the family Sciuridae (/sɪˈjuːrɪdeɪ, -diː/), a family that includes small or medium-sized rodents. The squirrel family includes...

The tomato (/təmeɪtoʊ/ or /təmɑːtoʊ/) is the edible berry of the plant Solanum lycopersicum, commonly known as the tomato plant. The species originated...

Masturbation is a form of autoeroticism in which a person sexually stimulates their own genitals for sexual arousal or other sexual pleasure, usually to...

A sex position is a positioning of the bodies that people use to engage in sexual intercourse or other sexual activities. Sexual acts are generally described...

Evolution is the change in the heritable characteristics of biological populations over successive generations. It occurs when evolutionary processes such...

Human sexual activity, human sexual practice or human sexual behaviour is the manner in which humans experience and express their sexuality. People engage...

The Labrador Retriever or simply Labrador is a British breed of retriever gun dog. It was developed in the United Kingdom from St. John's water dogs imported...

Prostitution is the business or practice of engaging in sexual activity in exchange for payment. The definition of "sexual activity" varies, and is often...

The avocado, alligator pear or avocado pear (Persea americana) is a medium-sized, evergreen tree in the laurel family (Lauraceae). It is native to the...

Oral sex, sometimes referred to as oral intercourse, is sexual activity involving the stimulation of the genitalia of a person by another person using...

Manihot esculenta, commonly called cassava (/kəˈsɑːvə/), manioc, yuca (among numerous regional names) is a woody shrub of the spurge family, Euphorbiaceae...

The wolverine (/ˈwʊlvəriːn/ WUUL-və-reen, US also /ˌwʊlvəˈriːn/ WUUL-və-REEN; Gulo gulo; Gulo is Latin for "glutton"), also referred to as the glutton...

Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins...

The cicadas (/sɪˈkɑːdəz, -ˈkeɪ-/) are a superfamily, the Cicadoidea, of insects in the order Hemiptera (true bugs). They are in the suborder Auchenorrhyncha...

Orchids are plants that belong to the family Orchidaceae (/ˌɔːrkɪˈdeɪsi.iː, -si.aɪ/), a diverse and widespread group of flowering plants with blooms that...

The breast is one of two prominences located on the upper ventral region of the torso among humans and other primates. Both sexes develop breasts from...

Human sexuality is the way people experience and express themselves sexually. This involves biological, psychological, physical, erotic, emotional, social...

The goat or domestic goat (Capra hircus) is a species of domesticated goat-antelope that is mostly kept as livestock. It was domesticated from the bezoar...

Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also includes the hares), which is in the order Lagomorpha...

In a multicellular organism, an organ is a collection of tissues joined in a structural unit to serve a common function. In the hierarchy of life, an organ...

The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in...

Beetles are insects that form the order Coleoptera (/koʊliːˈɒptərə/), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases...

Foxes are small- to medium-sized omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull; upright, triangular...

In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by...

Photosynthesis (/ˌfoʊtəˈsɪnθəsɪs/ FOH-tə-SINTH-ə-sis) is a system of biological processes by which photosynthetic organisms, such as most plants, algae...

The dachshund (UK: /ˈdækshʊnd, -ənd, -hʊnt/ DAKS-huund, -⁠ənd, -⁠huunt or US: /ˈdɑːkshʊnt, -hʊnd, -ənt/ DAHKS-huunt, -⁠huund, -⁠ənt; German: 'badger dog')...

Hyenas or hyaenas (/haɪˈiːnəz/ hi-EE-nəz; from Ancient Greek ὕαινα, hýaina) are feliform carnivoran mammals belonging to the family Hyaenidae /haɪˈɛnɪdiː/...

Vertebrates (/ˈvɜːrtəbrɪts, -ˌbreɪts/) are deuterostomal animals with bony or cartilaginous axial endoskeleton — known as the vertebral column, spine or...

Owls are birds from the order Strigiformes (/ˈstrɪdʒəfɔːrmiːz/), which includes over 200 species of mostly solitary and nocturnal birds of prey typified...

In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering (see Fruit anatomy). Fruits are the...

The beagle is a breed of small scent hound, similar in appearance to the much larger foxhound. The beagle was developed primarily for hunting hare, known...

Escherichia coli (/ˌɛʃəˈrɪkiə ˈkoʊlaɪ/ ESH-ə-RIK-ee-ə KOH-ly) is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus Escherichia...

Ecology (from Ancient Greek οἶκος (oîkos) 'house', and -λογία (-logía) 'study of') is the natural science of the relationships among living organisms,...

Sixty-nine or 69 is a sex position in which two people align themselves so that each person's mouth is near the other's genitals so that each partner can...

Rodents (from Latin rodere, 'to gnaw') are mammals of the order Rodentia (/roʊˈdɛnʃə/ roh-DEN-shə), which are characterized by a single pair of continuously...

A hermaphrodite (/hərˈmæfrəˌdaɪt/) is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are...

Algae (UK: /ˈælɡiː/ AL-ghee, US: /ˈældʒiː/ AL-jee; sg.: alga /ˈælɡə/ AL-gə) are any of a large and diverse group of photosynthetic, eukaryotic organisms...

Zoophilia is a paraphilia in which a person experiences a sexual fixation on non-human animals. Bestiality instead refers to cross-species sexual activity...

The peanut (Arachis hypogaea), also known as the groundnut, goober (US), goober pea, pindar (US) or monkey nut (UK), is a legume crop grown mainly for...

Endemism is the state of a species only being found in a single defined geographic location, such as an island, state, nation, country or other defined...

Biodiversity (or biological diversity) is the variety and variability of life on Earth. It can be measured on various levels. There is for example genetic...

Canidae (/ˈkænɪdiː/; from Latin, canis, "dog") is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade...

An organism's sex is female (symbol: ♀) if it produces the ovum (egg cell), the type of gamete (sex cell) that fuses with the male gamete (sperm cell)...

The National Center for Biotechnology Information (NCBI) is part of the United States National Library of Medicine (NLM), a branch of the National Institutes...

This article contains Linear B Unicode characters. Without proper rendering support, you may see question marks, boxes, or other symbols instead of Linear...

Extinction is the termination of a taxon by the death of its last member. A taxon may become functionally extinct before the death of its last member if...

Corals are colonial marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual...

Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus...

The wild boar (Sus scrofa), also known as the wild swine, common wild pig, Eurasian wild pig, or simply wild pig, is a suid native to much of Eurasia and...

Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese,...

Male (symbol: ♂) is the sex of an organism that produces the gamete (sex cell) known as sperm, which fuses with the larger female gamete, or ovum, in the...

The donkey is a domesticated equine. It derives from the African wild ass, Equus africanus, and may be classified either as a subspecies thereof, Equus...

Eggplant (US, CA, AU, NZ, PH), aubergine (UK, IE), brinjal (IN, SG, MY, ZA), or baigan (IN, GY) is a plant species in the nightshade family Solanaceae...

A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. Toadstool...

Paleontology (/ˌpeɪliɒnˈtɒlədʒi, ˌpæli-, -ən-/ PAY-lee-on-TOL-ə-jee, PAL-ee-, -⁠ən-), also spelled palaeontology or palæontology, is the scientific study...

A chromosome is a package of DNA with part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated...

Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to...

Non-penetrative sex or outercourse is sexual activity that usually does not include sexual penetration. It generally excludes the penetrative aspects of...

A rhinoceros (/raɪˈnɒsərəs/; from Ancient Greek ῥινόκερως (rhinókerōs) 'nose-horned'; from ῥίς (rhis) 'nose', and κέρας (kéras) 'horn'; pl.: rhinoceros...

Vascular plants (from Latin vasculum 'duct'), also called tracheophytes (/trəˈkiː.əˌfaɪts/) or collectively tracheophyta (/trəˈkiː.əfaɪtə/; from Ancient...

The moose (pl.: 'moose'; used in North America) or elk (pl.: 'elk' or 'elks'; used in Eurasia) (Alces alces) is the world's tallest, largest and heaviest...

The guinea pig or domestic guinea pig (Cavia porcellus), also known as the cavy or domestic cavy (/ˈkeɪvi/ KAY-vee), is a species of rodent belonging to...

Peafowl is a common name for two bird species of the genus Pavo and one species of the closely related genus Afropavo within the tribe Pavonini of the...

The Epstein–Barr virus (EBV), formally called Human gammaherpesvirus 4, is one of the nine known human herpesvirus types in the herpes family, and is one...

Sexual dimorphism is the condition where sexes of the same species exhibit different morphological characteristics, particularly characteristics not directly...

Tortoises (/ˈtɔːr.təs.ɪz/) are reptiles of the family Testudinidae of the order Testudines (Latin for "tortoise"). Like other turtles, tortoises have a...

A leaf (pl.: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally aboveground and specialized for photosynthesis....

The coconut tree (Cocos nucifera) is a member of the palm tree family (Arecaceae) and the only living species of the genus Cocos. The term "coconut" (or...

The Arecaceae (/ærəˈkeɪsiaɪ/) is a family of perennial, flowering plants in the monocot order Arecales. Their growth form can be climbers, shrubs, tree-like...

A cactus (pl.: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (/kæˈkteɪsiaɪ, -siːiː/), a family comprising about...

Rhododendron (/ˌroʊdəˈdɛndrən/; pl.: rhododendra) is a very large genus of about 1,024 species of woody plants in the heath family (Ericaceae). They can...

Eucalyptus (/ˌjuːkəˈlɪptəs/) is a genus of more than 700 species of flowering plants in the family Myrtaceae. Most species of Eucalyptus are trees, often...

An onion (Allium cepa L., from Latin cepa meaning "onion"), also known as the bulb onion or common onion, is a vegetable that is the most widely cultivated...

Intersex people are individuals born with any of several sex characteristics including chromosome patterns, gonads, or genitals that, according to the...

Watermelon (Citrullus lanatus) is a flowering plant species of the Cucurbitaceae family and the name of its edible fruit. A scrambling and trailing vine-like...

Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting tail-like abdomen, usually hidden entirely under...

The Cavalier King Charles Spaniel (CKCS) is a British breed of toy dog of spaniel type. Four colours are recognised: Blenheim (chestnut and white), tricolour...

Look up ejaculate in Wiktionary, the free dictionary. Ejaculation is the discharge of semen (the ejaculate; normally containing sperm) from the male reproductive...

Metabolism (/məˈtæbəlɪzəm/, from Greek: μεταβολή metabolē, "change") is the set of life-sustaining chemical reactions in organisms. The three main functions...

The fig is the edible fruit of Ficus carica, a species of small tree in the flowering plant family Moraceae, native to the Mediterranean region, together...

Genetics is the study of genes, genetic variation, and heredity in organisms. It is an important branch in biology because heredity is vital to organisms'...

Child pornography (also called CP, child sexual abuse material, CSAM, child porn, or kiddie porn) is erotic material that depicts persons under the age...

A passerine (/ˈpæsəraɪn/) is any bird of the order Passeriformes (/ˈpæsərɪfɔːrmiːz/; from Latin passer 'sparrow' and formis '-shaped') which includes more...

Norovirus, also known as Norwalk virus and sometimes referred to as the winter vomiting disease, is the most common cause of gastroenteritis. Infection...

The pineapple (Ananas comosus) is a tropical plant with an edible fruit; it is the most economically significant plant in the family Bromeliaceae. The...

The red fox (Vulpes vulpes) is the largest of the true foxes and one of the most widely distributed members of the order Carnivora, being present across...

Common lichen growth forms A lichen (/ˈlaɪkən/ LY-kən, UK also /ˈlɪtʃən/ LITCH-ən) is a symbiosis of algae or cyanobacteria living among filaments of multiple...

The cell is the basic structural and functional unit of all forms of life. Every cell consists of cytoplasm enclosed within a membrane; many cells contain...

A pornographic film actor or actress, pornographic performer, adult entertainer, or porn star is a person who performs sex acts on video that is usually...

Sadism and masochism, known collectively as sadomasochism (/ˌseɪdoʊˈmæsəkɪzəm/ SAY-doh-MASS-ə-kiz-əm), are the derivation of pleasure from acts of respectively...

In human anatomy, the penis (/ˈpiːnɪs/; pl.: penises or penes; from the Latin pēnis, initially "tail") is an external male sex organ (intromittent organ)...

Horticulture is the science, technology, art, and business of cultivating and using plants to improve human life. Horticulturists and Horticultural Scientists...

The sperm whale or cachalot (Physeter macrocephalus) is the largest of the toothed whales and the largest toothed predator. It is the only living member...

In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain...

A mouse (pl.: mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a...

The American black bear (Ursus americanus), also known as the black bear, is a species of medium-sized bear endemic to North America. It is the continent's...

The reindeer or caribou (Rangifer tarandus) is a species of deer with circumpolar distribution, native to Arctic, subarctic, tundra, boreal, and mountainous...

Cashew is the common name of a tropical evergreen tree Anacardium occidentale, in the family Anacardiaceae. It is native to South America and is the source...

Catfish (or catfishes; order Siluriformes /sɪˈljʊərɪfɔːrmiːz/ or Nematognathi) are a diverse group of ray-finned fish. Named for their prominent barbels...

The osprey (/ˈɒspri, -preɪ/; Pandion haliaetus), also called sea hawk, river hawk, and fish hawk, is a diurnal, fish-eating bird of prey with a cosmopolitan...

Smallpox was an infectious disease caused by variola virus (often called smallpox virus), which belongs to the genus Orthopoxvirus. The last naturally...

Taraxacum (/təˈræksəkəm/) is a large genus of flowering plants in the family Asteraceae, which consists of species commonly known as dandelions. The scientific...

A pine is any conifer tree or shrub in the genus Pinus (/ˈpaɪnuːs/) of the family Pinaceae. Pinus is the sole genus in the subfamily Pinoideae. World Flora...

Phoenix dactylifera, commonly known as the date palm, is a flowering-plant species in the palm family, Arecaceae, cultivated for its edible sweet fruit...

The pomegranate (Punica granatum) is a fruit-bearing deciduous shrub in the family Lythraceae, subfamily Punicoideae, that grows between 5 and 10 m (16...

Tardigrades (/ˈtɑːrdɪɡreɪdz/), known colloquially as water bears or moss piglets, are a phylum of eight-legged segmented micro-animals. They were first...

Meiosis (/maɪˈoʊsɪs/ ; from Ancient Greek μείωσις (meíōsis) 'lessening', since it is a reductional division) is a special type of cell division of germ...

Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia...

Gastropods (/ˈɡæstrəpɒdz/), commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda...

The axolotl (/ˈæksəlɒtəl/ ; from Classical Nahuatl: āxōlōtl [aːˈʃoːloːtɬ] ) (Ambystoma mexicanum) is a paedomorphic salamander closely related to the tiger...

Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (/pɪˈnɒfɪtə, ˈpaɪnoʊfaɪtə/)...

Symbiosis (from Greek συμβίωσις, symbíōsis, "living with, companionship, camaraderie", from σύν, sýn, "together", and βίωσις, bíōsis, "living") is any...

A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are seventeen species of hedgehog in five genera...

Cetacea (/sɪˈteɪʃə/; from Latin cetus 'whale', from Ancient Greek κῆτος (kêtos) 'huge fish, sea monster') is an infraorder of aquatic mammals belonging...

Incest (/ˈɪnsɛst/ IN-sest) is human sexual activity between family members or close relatives. This typically includes sexual activity between people in...

The carrot (Daucus carota subsp. sativus) is a root vegetable, typically orange in color, though heirloom variants including purple, black, red, white...

The lemon (Citrus × limon) is a species of small evergreen tree in the flowering plant family Rutaceae, native to Asia, primarily Northeast India (Assam)...

Pit bull is an umbrella term for several types of dog believed to have descended from bull and terriers. In the United States, the term is usually considered...

Artiodactyls are placental mammals belonging to the order Artiodactyla (/ˌɑːrtioʊˈdæktɪlə/ AR-tee-oh-DAK-tih-lə, from Ancient Greek ἄρτιος, ártios 'even'...

Salmon (/ˈsæmən/; pl.: salmon) is the common name for several commercially important species of euryhaline ray-finned fish from the genera Salmo and Oncorhynchus...

Fingering is sexual stimulation of the vulva (including the clitoris) or vagina by using the fingers. Vaginal fingering is legally and medically called...

Apes (collectively Hominoidea /hɒmɪˈnɔɪdi.ə/) are a clade of Old World simians native to sub-Saharan Africa and Southeast Asia (though they were more widespread...

Physiology (/ˌfɪziˈɒlədʒi/; from Ancient Greek φύσις (phúsis) 'nature, origin', and -λογία (-logía) 'study of') is the scientific study of functions and...

The family Asteraceae (/ˌæstəˈreɪsiiː, -siaɪ/), with the original name Compositae, consists of over 32,000 known species of flowering plants in over 1...

A honey bee (also spelled honeybee) is a eusocial flying insect within the genus Apis of the bee clade, all native to mainland Afro-Eurasia. After bees...

An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until...

The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. In botanical nomenclature, a synonym is a scientific name...

An alligator, or colloquially gator, is a large reptile in the genus Alligator of the family Alligatoridae of the order Crocodilia. The two extant species...

Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea that have adapted to occupy empty scavenged mollusc shells to protect their...

The cucumber (Cucumis sativus) is a widely-cultivated creeping vine plant in the family Cucurbitaceae that bears cylindrical to spherical fruits, which...

Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting...

The ferret (Mustela furo) is a small, domesticated species belonging to the family Mustelidae. The ferret is most likely a domesticated form of the wild...

A mangrove is a shrub or tree that grows mainly in coastal saline or brackish water. Mangroves grow in an equatorial climate, typically along coastlines...

The durian (/ˈdʊəriən/, /ˈdjʊəriən/) is the edible fruit of several tree species belonging to the genus Durio. There are 30 recognized Durio species, at...

Tamarind (Tamarindus indica) is a leguminous tree bearing edible fruit that is indigenous to tropical Africa and naturalized in Asia. The genus Tamarindus...

Hibiscus is a genus of flowering plants in the mallow family, Malvaceae. The genus is quite large, comprising several hundred species that are native to...

Columbidae (/kəˈlʌmbɪdiː/ kə-LUM-bih-dee) is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are...

Lepidoptera (/ˌlɛpɪˈdɒptərə/ LEP-ih-DOP-tər-ə) or lepidopterans is an order of winged insects that includes butterflies and moths. About 180,000 species...

Romance or romantic love is a feeling of love for, or a strong attraction towards another person, and the courtship behaviors undertaken by an individual...

The Maine Coon is a large domesticated cat breed. It is one of the oldest natural breeds in North America. The breed originated in the U.S. state of Maine...

In biology, taxonomic rank is the relative level of a group of organisms (a taxon) in an ancestral or hereditary hierarchy. A common system of biological...

The golden eagle (Aquila chrysaetos) is a bird of prey living in the Northern Hemisphere. It is the most widely distributed species of eagle. Like all...

The American bison (Bison bison; pl.: bison), also called the American buffalo or simply buffalo (not to be confused with true buffalo), is a species of...

Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and...

Sexual arousal (also known as sexual excitement) describes the physiological and psychological responses in preparation for sexual intercourse or when...

The Bulldog is a British breed of dog of mastiff type. It may also be known as the English Bulldog or British Bulldog. It is a medium-sized, muscular dog...

Albatrosses, of the biological family Diomedeidae, are large seabirds related to the procellariids, storm petrels, and diving petrels in the order Procellariiformes...

Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (/braɪˈɒfətə/, /ˌbraɪ.əˈfaɪtə/) sensu stricto. Bryophyta (sensu lato...

The peach (Prunus persica) is a deciduous tree first domesticated and cultivated in Zhejiang province of Eastern China. It bears edible juicy fruits with...

Tulips are spring-blooming perennial herbaceous bulbiferous geophytes in the Tulipa genus. Their flowers are usually large, showy, and brightly coloured...

Garlic (Allium sativum) is a species of bulbous flowering plant in the genus Allium. Its close relatives include the onion, shallot, leek, chive, Welsh...

The walrus (Odobenus rosmarus) is a large pinniped marine mammal with discontinuous distribution about the North Pole in the Arctic Ocean and subarctic...

The chickpea or chick pea (Cicer arietinum) is an annual legume of the family Fabaceae, subfamily Faboideae. Its different types are variously known as...

A red-light district or pleasure district is a part of an urban area where a concentration of prostitution and sex-oriented businesses, such as sex shops...

In biology, a kingdom is the second highest taxonomic rank, just below domain. Kingdoms are divided into smaller groups called phyla. Traditionally, some...

Gynaecology or gynecology (see American and British English spelling differences) is the area of medicine that involves the treatment of women's diseases...

A condom is a sheath-shaped barrier device used during sexual intercourse to reduce the probability of pregnancy or a sexually transmitted infection (STI)...

A bumblebee (or bumble bee, bumble-bee, or humble-bee) is any of over 250 species in the genus Bombus, part of Apidae, one of the bee families. This genus...

Within a nervous system, a neuron, neurone, or nerve cell is an electrically excitable cell that fires electric signals called action potentials across...

Equestrianism (from Latin equester, equestr-, equus, 'horseman', 'horse'), commonly known as horse riding (Commonwealth English) or horseback riding (American...

Insulin (/ˈɪn.sjʊ.lɪn/, from Latin insula, 'island') is a peptide hormone produced by beta cells of the pancreatic islets encoded in humans by the insulin...

A bison (pl.: bison) is a large bovine in the genus Bison (Greek: "wild ox" (bison)) within the tribe Bovini. Two extant and numerous extinct species are...

Pathology is the study of disease and injury. The word pathology also refers to the study of disease in general, incorporating a wide range of biology...

Ginkgo biloba, commonly known as ginkgo or gingko (/ˈɡɪŋkoʊ, ˈɡɪŋkɡoʊ/ GINK-oh, -⁠goh), also known as the maidenhair tree, is a species of gymnosperm tree...

Echidnas (/ɪˈkɪdnəz/), sometimes known as spiny anteaters, are quill-covered monotremes (egg-laying mammals) belonging to the family Tachyglossidae /tækiˈɡlɒsɪdiː/...

Manatees (/ˈmænətiːz/, family Trichechidae, genus Trichechus) are large, fully aquatic, mostly herbivorous marine mammals sometimes known as sea cows....

A sex organ, also known as a reproductive organ, is a part of an organism that is involved in sexual reproduction. Sex organs constitute the primary sex...

A carbohydrate (/ˌkɑːrboʊˈhaɪdreɪt/) is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom...

A fossil (from Classical Latin fossilis, lit. 'obtained by digging') is any preserved remains, impression, or trace of any once-living thing from a past...

Birds of prey or predatory birds, also known as raptors, are hypercarnivorous bird species that actively hunt and feed on other vertebrates (mainly mammals...

Lobsters are malacostracans of the family Nephropidae (synonym Homaridae). They have long bodies with muscular tails and live in crevices or burrows on...

The lentil (Vicia lens or Lens culinaris) is an edible legume. It is an annual plant known for its lens-shaped seeds. It is about 40 cm (16 in) tall, and...

This article contains Linear B Unicode characters. Without proper rendering support, you may see question marks, boxes, or other symbols instead of Linear...

Citrus is a genus of flowering trees and shrubs in the rue family, Rutaceae (/ruːˈteɪsiˌaɪ/). Plants in the genus produce citrus fruits, including crops...

The dingo (either included in the species Canis familiaris, or considered one of the following independent taxa: Canis familiaris dingo, Canis dingo, or...

Adenosine triphosphate (ATP) is a nucleotide that provides energy to drive and support many processes in living cells, such as muscle contraction, nerve...

Black pepper (Piper nigrum) is a flowering vine in the family Piperaceae, cultivated for its fruit (the peppercorn), which is usually dried and used as...

Molecular biology /məˈlɛkjʊlər/ is a branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including...

In biology, a taxon (back-formation from taxonomy; pl.: taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to...

In biology, epigenetics is the study of heritable traits, or a stable change of cell function, that happen without changes to the DNA sequence. The Greek...

Eels are ray-finned fish belonging to the order Anguilliformes (/æŋˈɡwɪlɪfɔːrmiːz/), which consists of eight suborders, 20 families, 164 genera, and about...

Pears are fruits produced and consumed around the world, growing on a tree and harvested in late summer into mid-autumn. The pear tree and shrub are a...

Deciduous forest In the fields of horticulture and botany, the term deciduous (/dɪˈsɪdʒu.əs/) means "falling off at maturity" and "tending to fall off"...

Salvia rosmarinus (/ˈsælviə ˌrɒsməˈraɪnəs/), commonly known as rosemary, is a shrub with fragrant, evergreen, needle-like leaves and white, pink, purple...

Prairie dogs (genus Cynomys) are herbivorous burrowing ground squirrels native to the grasslands of North America. There are five recognized species of...

The thylacine (/ˈθaɪləsiːn/; binomial name Thylacinus cynocephalus), also commonly known as the Tasmanian tiger or Tasmanian wolf, is an extinct carnivorous...

A sexually transmitted infection (STI), also referred to as a sexually transmitted disease (STD) and the older term venereal disease (VD), is an infection...

The llama (/ˈlɑːmə/; Spanish pronunciation: [ˈʎama] or [ˈʝama]) (Lama glama) is a domesticated South American camelid, widely used as a meat and pack animal...

A snail is a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name snail...

The Dobermann is a German breed of medium-large domestic dog of pinscher type. It was originally bred in Thuringia in about 1890 by Louis Dobermann, a...

Lettuce (Lactuca sativa) is an annual plant of the family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds...

Monitor lizards are lizards in the genus Varanus, the only extant genus in the family Varanidae. They are native to Africa, Asia, and Oceania, and one...

A pheromone (from Ancient Greek φέρω (phérō) 'to bear', and hormone) is a secreted or excreted chemical factor that triggers a social response in members...

The Canada goose (Branta canadensis), sometimes called Canadian goose, is a large wild goose with a black head and neck, white cheeks, white under its...

The citric acid cycle—also known as the Krebs cycle, Szent–Györgyi–Krebs cycle or the TCA cycle (tricarboxylic acid cycle)—is a series of biochemical reactions...

Millets (/ˈmɪlɪts/) are a highly varied group of small-seeded grasses, widely grown around the world as cereal crops or grains for fodder and human food...

Narcissus is a genus of predominantly spring flowering perennial plants of the amaryllis family, Amaryllidaceae. Various common names including daffodil...

The Rottweiler (/ˈrɒtwaɪlər/, UK also /-vaɪlər/, German: [ˈʁɔtvaɪ̯lɐ] ) is a breed of domestic dog, regarded as medium-to-large or large. The dogs were...

The stoat (Mustela erminea), also known as the Eurasian ermine, Beringian ermine and ermine, is a mustelid native to Eurasia and the northern regions of...

The Pomeranian (also known as a Pom, Pommy or Pome) is a breed of dog of the Spitz type that is named for the Pomerania region in north-west Poland and...

A tetrapod (/ˈtɛtrəˌpɒd/; from Ancient Greek τετρα- (tetra-) 'four', and πούς (poús) 'foot') is any four-limbed vertebrate animal of the superclass Tetrapoda...

Cloves are the aromatic flower buds of a tree in the family Myrtaceae, Syzygium aromaticum (/sɪˈzɪdʒiːəm ˌærəˈmætɪkəm/). They are native to the Maluku...

The Fabaceae (/fəˈbeɪsi.iː, -ˌaɪ/) or Leguminosae, commonly known as the legume, pea, or bean family, are a large and agriculturally important family of...

A biome (/ˈbaɪ.oʊm/) is a distinct geographical region with specific climate, vegetation, and animal life. It consists of a biological community that has...

Mitosis (/maɪˈtoʊsɪs/) is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division by mitosis is an equational...

Virginity is the state of a person who has never engaged in sexual intercourse. The term virgin originally only referred to sexually inexperienced women...

The human genome is a complete set of nucleic acid sequences for humans, encoded as DNA within the 23 chromosome pairs in cell nuclei and in a small DNA...

In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or...

The papaya (/pəˈpaɪə/, US: /pəˈpɑːjə/), papaw, (/pəˈpɔː/) or pawpaw (/ˈpɔːpɔː/) is the plant species Carica papaya, one of the 21 accepted species in the...

The sweet potato (Ipomoea batatas) is a dicotyledonous plant that belongs to the bindweed or morning glory family, Convolvulaceae. Its large, starchy,...

Human evolution is the evolutionary process within the history of primates that led to the emergence of Homo sapiens as a distinct species of the hominid...

Pea (Pisum in Latin) is a pulse, vegetable or fodder crop, but the word often refers to the seed or sometimes the pod of this flowering plant species,...

The king cobra (Ophiophagus hannah) is a venomous snake endemic to Asia. The sole member of the genus Ophiophagus, it is not taxonomically a true cobra...

Hares and jackrabbits are mammals belonging to the genus Lepus. They are herbivores, and live solitarily or in pairs. They nest in slight depressions called...

Lilium (/ˈlɪliəm/ LIL-ee-əm) is a genus of herbaceous flowering plants growing from bulbs, all with large and often prominent flowers. They are the true...

A zoo (short for zoological garden; also called an animal park or menagerie) is a facility in which animals are kept within enclosures for public exhibition...

Parsley, or garden parsley (Petroselinum crispum) is a species of flowering plant in the family Apiaceae that is native to Greece, Morocco and the former...

Hemoglobin (haemoglobin, Hb or Hgb) is a protein containing iron that facilitates the transport of oxygen in red blood cells. Almost all vertebrates contain...

Staphylococcus aureus is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body,...

Lavandula (common name lavender) is a genus of 47 known species of perennial flowering plants in the mints family, Lamiaceae. It is native to the Old World...

In biology, phylogenetics (/ˌfaɪloʊdʒəˈnɛtɪks, -lə-/) is the study of the evolutionary history and relationships among or within groups of organisms. These...

Sesame (/ˈsɛsəmi/; Sesamum indicum) is a plant in the genus Sesamum, also called benne or gingelly. Numerous wild relatives occur in Africa and a smaller...

The white-tailed deer (Odocoileus virginianus), also known commonly as the whitetail and the Virginia deer, is a medium-sized species of deer native to...

Chrysanthemums (/krɪˈsænθəməmz/ kriss-AN-thə-məmz), sometimes called mums or chrysanths, are flowering plants of the genus Chrysanthemum in the family...

The house mouse (Mus musculus) is a small mammal of the order Rodentia, characteristically having a pointed snout, large rounded ears, and a long and almost...

Necrophilia, also known as necrophilism, necrolagnia, necrocoitus, necrochlesis, and thanatophilia, is sexual attraction or acts involving corpses. It...

Chili peppers, also spelled chile or chilli (from Classical Nahuatl chīlli [ˈt͡ʃiːlːi] ), are varieties of the berry-fruit of plants from the genus Capsicum...

A shrub or bush is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs...

In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, species or genera through sexual...

This article contains special characters. Without proper rendering support, you may see question marks, boxes, or other symbols. Cumin (/ˈkʌmɪn/, /ˈkjuːmɪn/;...

Morus, a genus of flowering plants in the family Moraceae, consists of diverse species of deciduous trees commonly known as mulberries, growing wild and...

A tabby cat, or simply tabby, is any domestic cat (Felis catus) with a distinctive M-shaped marking on their forehead, stripes by their eyes and across...

Crayfish are freshwater crustaceans belonging to the infraorder Astacidea, which also contains lobsters. Taxonomically, they are members of the superfamilies...

A pet, or companion animal, is an animal kept primarily for a person's company or entertainment rather than as a working animal, livestock, or a laboratory...

Anise (/ˈænɪs/; Pimpinella anisum), also called aniseed or rarely anix, is a flowering plant in the family Apiaceae native to the eastern Mediterranean...

The pistachio (/pɪˈstɑːʃi.oʊ, -ˈstæʃ-/ pih-STAH-shee-oh, -⁠STASH-; Pistacia vera), a member of the cashew family, is a small tree originating in Persia...

Porcupines are large rodents with coats of sharp spines, or quills, that protect them against predation. The term covers two families of animals: the Old...

A tuna (pl.: tunas or tuna) is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae (mackerel) family. The Thunnini comprise...

In biological classification, subspecies (pl.: subspecies) is a rank below species, used for populations that live in different areas and vary in size...

Tarantulas comprise a group of large and often hairy spiders of the family Theraphosidae. As of December 2023[update], 1,100 species have been identified...

Nucleic acids are large biomolecules that are crucial in all cells and viruses. They are composed of nucleotides, which are the monomer components: a 5-carbon...

Entomology (from Ancient Greek ἔντομον (entomon) 'insect', and -λογία (-logia) 'study') is the scientific study of insects, a branch of zoology. In the...

Gram-negative bacteria are bacteria that unlike gram-positive bacteria do not retain the crystal violet stain used in the Gram staining method of bacterial...

Procuring, pimping, or pandering is the facilitation or provision of a prostitute or other sex worker in the arrangement of a sex act with a customer....

An antibody (Ab) is the secreted form of a B cell receptor; the term immunoglobulin (Ig) can refer to either the membrane-bound form or the secreted form...

Swinging, sometimes called wife-swapping, husband-swapping, or partner-swapping, is a sexual activity in which both singles and partners in a committed...

Cuckoos are birds in the Cuculidae /kjuːˈkjuːlɪdiː/ family, the sole taxon in the order Cuculiformes /kjuːˈkjuːlɪfɔːrmiːz/. The cuckoo family includes...

Basil (/ˈbæzəl/, also US: /ˈbeɪzəl/; Ocimum basilicum /ˈɒsɪməm bəˈzɪlɪkəm/), also called great basil, is a culinary herb of the family Lamiaceae (mints)...

Bioinformatics (/ˌbaɪ.oʊˌɪnfərˈmætɪks/ ) is an interdisciplinary field of science that develops methods and software tools for understanding biological...

In genetics, the phenotype (from Ancient Greek φαίνω (phaínō) 'to appear, show', and τύπος (túpos) 'mark, type') is the set of observable characteristics...

Look up epithelium or squamous in Wiktionary, the free dictionary. Epithelium or epithelial tissue is a thin, continuous, protective layer of compactly...

Human papillomavirus infection (HPV infection) is caused by a DNA virus from the Papillomaviridae family. Many HPV infections cause no symptoms and 90%...

Amniotes are tetrapod vertebrate animals belonging to the clade Amniota, a large group that comprises the vast majority of living terrestrial and semiaquatic...

Huntsman spiders, members of the family Sparassidae (formerly Heteropodidae), are known by this name because of their speed and mode of hunting.[citation...

Grasshoppers are a group of insects belonging to the suborder Caelifera. They are amongst what are possibly the most ancient living groups of chewing herbivorous...

In biology, homeostasis (British also homoeostasis; /hɒmioʊˈsteɪsɪs, -miə-/) is the state of steady internal physical and chemical conditions maintained...

Asparagus (Asparagus officinalis) is a perennial flowering plant species in the genus Asparagus native to Eurasia. Widely cultivated as a vegetable crop...

The grizzly bear (Ursus arctos horribilis), also known as the North American brown bear or simply grizzly, is a population or subspecies of the brown bear...

A prion /ˈpriːɒn/ is a misfolded protein that can induce misfolding of normal variants of the same protein and trigger cellular death. Prions cause prion...

A forest is an ecosystem characterized by a dense community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors...

Hemiptera (/hɛˈmɪptərə/; from Ancient Greek hemipterus 'half-winged') is an order of insects, commonly called true bugs, comprising over 80,000 species...

Quinoa (Chenopodium quinoa; /ˈkiːn.wɑː, kiˈnoʊ.ə/, from Quechua kinwa or kinuwa) is a flowering plant in the amaranth family. It is a herbaceous annual...

A cultivar is a kind of cultivated plant that people have selected for desired traits and which retains those traits when propagated. Methods used to propagate...

Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly...

The raspberry is the edible fruit of a multitude of plant species in the genus Rubus of the rose family, most of which are in the subgenus Idaeobatus....

Eye color is a polygenic phenotypic trait determined by two factors: the pigmentation of the eye's iris and the frequency-dependence of the scattering...

The Shih Tzu (UK: /ˌʃiːˈtsuː/, US: /ˈʃiːtsuː/; Chinese: 西施犬; pinyin: Xī Shī quǎn literally "Hsi Shih dog") is a toy dog or pet dog breed originating from...

The peony or paeony (/ˈpiːəni/) is any flowering plant in the genus Paeonia, the only genus in the family Paeoniaceae. Peonies are native to Asia, Europe...

Nutrition is the biochemical and physiological process by which an organism uses food to support its life. It provides organisms with nutrients, which...

Sea turtles (superfamily Chelonioidea), sometimes called marine turtles, are reptiles of the order Testudines and of the suborder Cryptodira. The seven...

Sperm (pl.: sperm or sperms) is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female...

Erectile dysfunction (ED), also referred to as impotence, is a form of sexual dysfunction in males characterized by the persistent or recurring inability...

The Pug is a breed of dog with the physically distinctive features of a wrinkly, short-muzzled face, and curled tail. An ancient breed, with roots dating...

Swans are birds of the genus Cygnus within the family Anatidae. The swans' closest relatives include the geese and ducks. Swans are grouped with the closely...

Taiga (/ˈtaɪɡə/; Russian: тайга́), also known as boreal forest or snow forest, is a biome characterized by coniferous forests consisting mostly of pines...

In biological phylogenetics, a clade (from Ancient Greek κλάδος (kládos) 'branch'), also known as a monophyletic group or natural group, is a grouping...

Cuttlefish, or cuttles, are marine molluscs of the order Sepiida. They belong to the class Cephalopoda which also includes squid, octopuses, and nautiluses...

Rapeseed (Brassica napus subsp. napus), also known as oilseed rape, is a bright-yellow flowering member of the family Brassicaceae (mustard or cabbage...

Sarcopterygii (/ˌsɑːrkɒptəˈrɪdʒi.aɪ/; from Ancient Greek σάρξ (sárx) 'flesh', and πτέρυξ (ptérux) 'wing, fin') — sometimes considered synonymous with Crossopterygii...

Protozoa (sg.: protozoan or protozoon; alternative plural: protozoans) are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic...

Kiwi (/ˈkiːwiː/ KEE-wee) are flightless birds endemic to New Zealand of the order Apterygiformes. The five extant species fall into the family Apterygidae...

The Border Collie is a British breed of herding dog of the collie type of medium size. It originates in the region of the Anglo-Scottish border, and descends...

Deuterostomes (from Greek: lit. 'mouth second') are bilaterian animals of the superphylum Deuterostomia (/ˌdjuːtərəˈstoʊmi.ə/), typically characterized...

An ox /ˈɒks/ OKS (pl.: oxen, /ˈɒksən/ OK-sen), also known as a bullock (in British, Australian, and Indian English), is a bovine, trained and used as a...

An apricot (US: /ˈæprɪkɒt/ , UK: /ˈeɪprɪkɒt/ ) is a fruit, or the tree that bears the fruit, of several species in the genus Prunus. Usually an apricot...

Flax, also known as common flax or linseed, is a flowering plant, Linum usitatissimum, in the family Linaceae. It is cultivated as a food and fiber crop...

Liquorice (British English) or licorice (American English; IPA: /ˈlɪkərɪʃ, -ɪs/ LIK-ər-ish, -⁠iss) is the common name of Glycyrrhiza glabra, a flowering...

Paprika (US /pəˈprikə/, /pæˈprikə/ ; UK /ˈpæprɪkə/, /pəˈpriːkə/) is a spice made from dried and ground red peppers. It is traditionally made from Capsicum...

Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete (haploid reproductive cells, such as a sperm or egg...

Cellular respiration is the process by which biological fuels are oxidized in the presence of an inorganic electron acceptor, such as oxygen, to drive...

An aquarium (pl.: aquariums or aquaria) is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and...

The anglerfish are fish of the teleost order Lophiiformes (/ˌlɒfiɪˈfɔːrmiːz/). They are bony fish named for their characteristic mode of predation, in...

The Jack Russell Terrier is a British breed of small terrier. It is principally white-bodied and smooth-, rough- or broken-coated, and can be any colour...

The Solanaceae (/ˌsɒləˈneɪsi.iː, -ˌaɪ/), or the nightshades, are a family of flowering plants that ranges from annual and perennial herbs to vines, lianas...

An inflorescence, in a flowering plant, is a group or cluster of flowers arranged on a stem that is composed of a main branch or a system of branches....

The mule is a domestic equine hybrid between a donkey and a horse. It is the offspring of a male donkey (a jack) and a female horse (a mare). The horse...

A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component...

Magnolia is a large genus of about 210 to 340 flowering plant species in the subfamily Magnolioideae of the family Magnoliaceae. The natural range of Magnolia...

In biology, tissue is an assembly of similar cells and their extracellular matrix from the same embryonic origin that together carry out a specific function...

Blueberry is a widely distributed and widespread group of perennial flowering plant with blue or purple berries. They are classified in the section Cyanococcus...

The yak (Bos grunniens), also known as the Tartary ox, grunting ox, or hairy cattle, is a species of long-haired domesticated cattle found throughout the...

Lipids are a broad group of organic compounds which include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides...

Coelacanths (/ˈsiːləkænθ/ SEE-lə-kanth) (order Coelacanthiformes) are an ancient group of lobe-finned fish (Sarcopterygii) in the class Actinistia. As...

The red deer (Cervus elaphus) is one of the largest deer species. A male red deer is called a stag or hart, and a female is called a doe or hind. The red...

Salmonella is a genus of rod-shaped (bacillus) gram-negative bacteria of the family Enterobacteriaceae. The two known species of Salmonella are Salmonella...

The water buffalo (Bubalus bubalis), also called the domestic water buffalo or Asian water buffalo, is a large bovid originating in the Indian subcontinent...

A hormone (from the Greek participle ὁρμῶν, "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant...

Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described...

The saltwater crocodile (Crocodylus porosus) is a crocodilian native to saltwater habitats, brackish wetlands and freshwater rivers from India's east coast...

Yellow fever is a viral disease of typically short duration. In most cases, symptoms include fever, chills, loss of appetite, nausea, muscle pains—particularly...

The beluga whale (/bɪˈluːɡə/; Delphinapterus leucas) is an Arctic and sub-Arctic cetacean. It is one of two members of the family Monodontidae, along with...

Examples of albino laboratory mammals Albinism is the congenital absence of melanin in an animal or plant resulting in white hair, feathers, scales and...

The rosids are members of a large clade (monophyletic group) of flowering plants, containing about 70,000 species, more than a quarter of all angiosperms...

Livestock are the domesticated animals raised in an agricultural setting in order to provide labour and produce diversified products for consumption such...

Foot fetishism, also known as foot partialism or podophilia, is a pronounced sexual interest in feet. It is the most common form of sexual fetishism for...

The Integrated Taxonomic Information System (ITIS) is an American partnership of federal agencies designed to provide consistent and reliable information...

Promiscuity is the practice of engaging in sexual activity frequently with different partners or being indiscriminate in the choice of sexual partners...

Willows, also called sallows and osiers, of the genus Salix, comprise around 350 species (plus numerous hybrids) of typically deciduous trees and shrubs...

Hawks are birds of prey of the family Accipitridae. They are very widely distributed and are found on all continents except Antarctica. The subfamily Accipitrinae...

A seahorse (also written sea-horse and sea horse) is any of 46 species of small marine bony fish in the genus Hippocampus. "Hippocampus" comes from the...

Kelps are large brown algae or seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance, kelp is not a...

Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists...

Sexual penetration is the insertion of a body part or other object into a body orifice, such as the mouth, vagina or anus, as part of human sexual activity...

Pangolins, sometimes known as scaly anteaters, are mammals of the order Pholidota (/fɒlɪˈdoʊtə/). The one extant family, the Manidae, has three genera:...

Nucleotides are organic molecules composed of a nitrogenous base, a pentose sugar and a phosphate. They serve as monomeric units of the nucleic acid polymers...

Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. By analogy, the...

Celery (Apium graveolens) is a marshland plant in the family Apiaceae that has been cultivated as a vegetable since ancient times. Celery has a long fibrous...

Fermentation is a metabolic process that produces chemical changes in organic substances through the action of enzymes. In biochemistry, it is broadly...

The turkey is a large bird in the genus Meleagris, native to North America. There are two extant turkey species: the wild turkey (Meleagris gallopavo)...

The wild turkey (Meleagris gallopavo) is an upland game bird native to North America, one of two extant species of turkey and the heaviest member of the...

A seed plant or spermatophyte (lit. 'seed plant'; from Ancient Greek σπέρματος (spérmatos) 'seed', and φυτόν (phytón) 'plant'), also known as a phanerogam...

In biology, a phylum (/ˈfaɪləm/; pl.: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the...

A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form...

CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is...

The embryophytes (/ˈɛmbriəˌfaɪts/) are a clade of plants, also known as Embryophyta (/ˌɛmbriˈɒfətə, -oʊˈfaɪtə/) or land plants. They are the most familiar...

The endoplasmic reticulum (ER) is a part of a transportation system of the eukaryotic cell, and has many other important functions such as protein folding...

A piranha or piraña (/pɪˈrɑːnjəˌ -ræn/, or /pɪˈrɑːnə/; Portuguese: [piˈɾɐ̃ɲɐ], Spanish: [piˈɾaɲa]) is any of a number of freshwater fish species in the...

A sex toy is an object or device that is primarily used to facilitate sexual pleasure, such as a dildo, artificial vagina or vibrator. Many popular sex...

Transcription is the process of copying a segment of DNA into RNA. The segments of DNA transcribed into RNA molecules that can encode proteins produce...

This article contains special characters. Without proper rendering support, you may see question marks, boxes, or other symbols. Fennel (Foeniculum vulgare)...

A nut is a fruit consisting of a hard or tough nutshell protecting a kernel which is usually edible. In general usage and in a culinary sense, a wide variety...

Lampreys /ˈlæmpreɪz/ (sometimes inaccurately called lamprey eels) are a group of jawless fish comprising the order Petromyzontiformes /ˌpɛtroʊmɪˈzɒntɪfɔːrmiːz/...

Mycology is the branch of biology concerned with the study of fungi, including their taxonomy, genetics, biochemical properties, and use by humans. Fungi...

The age of consent is the age at which a person is considered to be legally competent to consent to sexual acts. Consequently, an adult who engages in...

The Great Dane is a German breed of large mastiff-sighthound, which descends from hunting dogs of the Middle Ages used to hunt bears, wild boar, and deer...

In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid...

Pharmacology is the science of drugs and medications, including a substance's origin, composition, pharmacokinetics, pharmacodynamics, therapeutic use...

The bull shark (Carcharhinus leucas), also known as the Zambezi shark (informally zambi) in Africa and Lake Nicaragua shark in Nicaragua, is a species...

The fisher (Pekania pennanti) is a carnivorous mammal native to North America, a forest-dwelling creature whose range covers much of the boreal forest...

Cassowaries (Tok Pisin: muruk, Indonesian: kasuari) are flightless birds of the genus Casuarius in the order Casuariiformes. They are classified as ratites:...

The Bengal tiger is a population of the Panthera tigris tigris subspecies and the nominate tiger subspecies. It ranks among the biggest wild cats alive...

In psychology, libido (/lɪˈbiːdoʊ/; from the Latin libīdō, 'desire') is psychic drive or energy, usually conceived as sexual in nature, but sometimes conceived...

The rectum (pl.: rectums or recta) is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. The adult...

Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food...

An earthworm is a soil-dwelling terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the...

Porpoises (/ˈpɔːrpəsɪz/) are small dolphin-like cetaceans classified under the family Phocoenidae. Although similar in appearance to dolphins, they are...

The grapefruit (Citrus × paradisi) is a subtropical citrus tree known for its relatively large, sour to semi-sweet, somewhat bitter fruit. The interior...

DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is...

The Siamese cat (Thai: แมวไทย, Maeo Thai; แมวสยาม, Maeo Sayam) is one of the first distinctly recognised breeds of Asian cat. Derived from the Wichianmat...

The sugar glider (Petaurus breviceps) is a small, omnivorous, arboreal, and nocturnal gliding possum. The common name refers to its predilection for sugary...

Archosauria (lit. 'ruling reptiles') is a clade of diapsid sauropsid tetrapods, with birds and crocodilians being the only living representatives. Archosaurs...

Coatis (from Tupí), also known as coatimundis (/koʊˌɑːtɪˈmʌndi/), are members of the family Procyonidae in the genera Nasua and Nasuella (comprising the...

Immunology is a branch of biology and medicine that covers the study of immune systems in all organisms. Immunology charts, measures, and contextualizes...

Bird flight is the primary mode of locomotion used by most bird species in which birds take off and fly. Flight assists birds with feeding, breeding, avoiding...

A lemming is a small rodent, usually found in or near the Arctic in tundra biomes. Lemmings form the subfamily Arvicolinae (also known as Microtinae) together...

Apoptosis (from Ancient Greek: ἀπόπτωσις, romanized: apóptōsis, lit. 'falling off') is a form of programmed cell death that occurs in multicellular organisms...

The rock dove, rock pigeon, or common pigeon (/ˈpɪdʒ.ən/ also /ˈpɪdʒ.ɪn/; Columba livia) is a member of the bird family Columbidae (doves and pigeons)...

A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include T cells (for cell-mediated and cytotoxic...

A father is the male parent of a child. Besides the paternal bonds of a father to his children, the father may have a parental, legal, and social relationship...

In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally...

The Greyhound is a breed of dog, a sighthound which has been bred for coursing, greyhound racing and hunting. Since the rise in large-scale adoption of...

Cranes are a type of large bird with long legs and necks in the biological family Gruidae of the order Gruiformes. The family has 15 species placed in...

Archaeopteryx (/ˌɑːrkiːˈɒptərɪks/; lit. 'old-wing'), sometimes referred to by its German name, "Urvogel" (lit. Primeval Bird) is a genus of bird-like dinosaurs...

In common law jurisdictions, statutory rape is nonforcible sexual activity in which one of the individuals is below the age of consent (the age required...

Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species,...

The Bengal cat is a breed of hybrid cat created from crossing of an Asian leopard cat (Prionailurus bengalensis), with domestic cats, especially the spotted...

A walnut is the edible seed of any tree of the genus Juglans (family Juglandaceae), particularly the Persian or English walnut, Juglans regia. They are...

In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is...

The Yorkshire Terrier, also known as a Yorkie, is a British breed of toy dog of terrier type. It is among the smallest of the terriers and indeed of all...

Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species...

Anthropomorphism is the attribution of human traits, emotions, or intentions to non-human entities. It is considered to be an innate tendency of human...

Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii, an apicomplexan. Infections with toxoplasmosis are associated with a variety of neuropsychiatric...

Nudibranchs (/ˈnjuːdɪbræŋk/) belong to the order Nudibranchia, a group of soft-bodied marine gastropod molluscs that shed their shells after their larval...

The blackberry is an edible fruit produced by many species in the genus Rubus in the family Rosaceae, hybrids among these species within the subgenus Rubus...

Habitat destruction (also termed habitat loss and habitat reduction) occurs when a natural habitat is no longer able to support its native species. The...

Sea lions are pinnipeds characterized by external ear flaps, long foreflippers, the ability to walk on all fours, short and thick hair, and a big chest...

Morchella, the true morels, is a genus of edible sac fungi closely related to anatomically simpler cup fungi in the order Pezizales (division Ascomycota)...

In botany, an evergreen is a plant which has foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which...

Phalacrocoracidae is a family of approximately 40 species of aquatic birds commonly known as cormorants and shags. Several different classifications of...

Chlorophyll at different scales Chlorophyll is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants...

Hoverflies, also called flower flies or syrphids, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring...

Glycolysis is the metabolic pathway that converts glucose (C6H12O6) into pyruvate and, in most organisms, occurs in the liquid part of cells (the cytosol)...

Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other...

This article contains Ethiopic text. Without proper rendering support, you may see question marks, boxes, or other symbols instead of Ethiopic characters...

Red blood cells (RBCs), scientific name erythrocytes (from ancient Greek erythros 'red' and kytos 'hollow vessel', with -cyte translated as 'cell' in modern...

Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and...

Ploidy (/ˈplɔɪdi/) is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal...

In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest...

Cock and ball torture (CBT) is a sexual activity involving the application of pain or constriction to the male genitals. This may involve directly painful...

A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently for years or decades or seasonally for a shorter periods. Flooding...

A diatom (Neo-Latin diatoma) is any member of a large group comprising several genera of algae, specifically microalgae, found in the oceans, waterways...

Capsicum (/ˈkæpsɪkəm/) is a genus of flowering plants in the nightshade family Solanaceae, native to the Americas, cultivated worldwide for their edible...

Herpes simplex virus 1 and 2 (HSV-1 and HSV-2), also known by their taxonomic names Human alphaherpesvirus 1 and Human alphaherpesvirus 2, are two members...

A bacteriophage (/bækˈtɪərioʊfeɪdʒ/), also known informally as a phage (/ˈfeɪdʒ/), is a virus that infects and replicates within bacteria and archaea....

Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits...

Mussel (/ˈmʌsəl/) is the common name used for members of several families of bivalve molluscs, from saltwater and freshwater habitats. These groups have...

A vulture is a bird of prey that scavenges on carrion. There are 23 extant species of vulture (including Condors). Old World vultures include 16 living...

Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds. Pollinating...

Ficus (/ˈfaɪkəs/ or /ˈfiːkəs/) is a genus of about 850 species of woody trees, shrubs, vines, epiphytes and hemiepiphytes in the family Moraceae. Collectively...

The missionary position or man-on-top position is a sex position in which, generally, a woman lies on her back and spreads her legs and a man lies on top...

Sumac or sumach (/ˈsuːmæk, ˈʃuː-/ S(H)OO-mak, UK also /ˈsjuː-/) is any of about 35 species of flowering plants in the genus Rhus and related genera in...

A skeleton is the structural frame that supports the body of most animals. There are several types of skeletons, including the exoskeleton, which is a...

The North American beaver (Castor canadensis) is one of two extant beaver species, along with the Eurasian beaver (Castor fiber). It is native to North...

A circadian rhythm (/sərˈkeɪdiən/), or circadian cycle, is a natural oscillation that repeats roughly every 24 hours. Circadian rhythms can refer to any...

A sense is a biological system used by an organism for sensation, the process of gathering information about the surroundings through the detection of...

The okapi (/oʊˈkɑːpiː/; Okapia johnstoni), also known as the forest giraffe, Congolese giraffe and zebra giraffe, is an artiodactyl mammal that is endemic...

The sable (Martes zibellina) is a species of marten, a small omnivorous mammal primarily inhabiting the forest environments of Russia, from the Ural Mountains...

Basidiomycota (/bəˌsɪdi.oʊmaɪˈkoʊtə/) is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred...

Melatonin, an indoleamine, is a natural compound produced by various organisms, including bacteria and eukaryotes. Its discovery in 1958 by Aaron B. Lerner...

Tetraodontidae is a family of primarily marine and estuarine fish of the order Tetraodontiformes. The family includes many familiar species variously called...

The nutria or coypu (Myocastor coypus) is a large, herbivorous, semiaquatic rodent from South America. Classified for a long time as the only member of...

The radish (Raphanus raphanistrum subsp. sativus) is an edible root vegetable of the mustard family, Brassicaceae, that was domesticated in Asia prior...

Heredity, also called inheritance or biological inheritance, is the passing on of traits from parents to their offspring; either through asexual reproduction...

Ebola, also known as Ebola virus disease (EVD) and Ebola hemorrhagic fever (EHF), is a viral hemorrhagic fever in humans and other primates, caused by...

Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to...

Avian malaria is a parasitic disease of birds, caused by parasite species belonging to the genera Plasmodium and Hemoproteus (phylum Apicomplexa, class...

Monogamy (/məˈnɒɡəmi/ mə-NOG-ə-mee) is a relationship of two individuals in which they form an exclusive intimate partnership. Having only one partner...

Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family called Ciconiidae, and make up the order Ciconiiformes...

Sexual attraction is attraction on the basis of sexual desire or the quality of arousing such interest. Sexual attractiveness or sex appeal is an individual's...

Tilapia (/tɪˈlɑːpiə/ tih-LAH-pee-ə) is the common name for nearly a hundred species of cichlid fish from the coelotilapine, coptodonine, heterotilapine...

The leatherback sea turtle (Dermochelys coriacea), sometimes called the lute turtle, leathery turtle or simply the luth, is the largest of all living turtles...

The opisthokonts (from Ancient Greek ὀπίσθιος (opísthios) 'rear, posterior', and κοντός (kontós) 'pole, i.e. flagellum') are a broad group of eukaryotes...

Female ejaculation is characterized as an expulsion of fluid from the Skene's gland at the lower end of the urethra during or before an orgasm. It is also...

The Lamiaceae (/ˌleɪmiˈeɪsiːˌiː, -iˌaɪ/ LAY-mee-AY-see-ee, -⁠eye) or Labiatae are a family of flowering plants commonly known as the mint, deadnettle or...

Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton...

Postsynaptic density Voltage- gated Ca++ channel Synaptic vesicle Neurotransmitter transporter Receptor Neurotransmitter Axon terminal Synaptic cleft Dendrite...

The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina)...

Asparagales (asparagoid lilies) is an order of plants in modern classification systems such as the Angiosperm Phylogeny Group (APG) and the Angiosperm...

Selective breeding (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular...

The domestic pigeon (Columba livia domestica or Columba livia forma domestica) is a pigeon subspecies that was derived from the rock dove or rock pigeon...

Tubers are a type of enlarged structure used as storage organs for nutrients in some plants, derived from stems or roots. Tubers help plants perennate...

The giant squid (Architeuthis dux) is a species of deep-ocean dwelling squid in the family Architeuthidae. It can grow to a tremendous size, offering an...

The budgerigar (/ˈbʌdʒərɪˌɡɑːr, -əriː-/ BUJ-ər-ih-gar, -⁠ə-ree-; Melopsittacus undulatus), also known as the common parakeet, shell parakeet or budgie...

Mendelian inheritance (also known as Mendelism) is a type of biological inheritance following the principles originally proposed by Gregor Mendel in 1865...

A gazelle is one of many antelope species in the genus Gazella /ɡəˈzɛlə/. There are also seven species included in two further genera; Eudorcas and Nanger...

Slug, or land slug, is a common name for any apparently shell-less terrestrial gastropod mollusc. The word slug is also often used as part of the common...

A flagellum (/fləˈdʒɛləm/; pl.: flagella) (Latin for 'whip' or 'scourge') is a hairlike appendage that protrudes from certain plant and animal sperm cells...

Milk is a white liquid food produced by the mammary glands of mammals and the caecilian Siphonops annulatus. It is the primary source of nutrition for...

The bowhead whale (Balaena mysticetus) is a species of baleen whale belonging to the family Balaenidae and is the only living representative of the genus...

In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can change into various types of cells and proliferate...

Cell division is the process by which a parent cell divides into two daughter cells. Cell division usually occurs as part of a larger cell cycle in which...

The turnip or white turnip (Brassica rapa subsp. rapa) is a root vegetable commonly grown in temperate climates worldwide for its white, fleshy taproot...

A sepal (/ˈsɛpəl, ˈsiːpəl/) is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower...

In biology, homology is similarity due to shared ancestry between a pair of structures or genes in different taxa. A common example of homologous structures...

Galliformes /ˌɡælɪˈfɔːrmiːz/ is an order of heavy-bodied ground-feeding birds that includes turkeys, chickens, quail, and other landfowl. Gallinaceous...

In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name organelle comes from the idea that...

Kumquats (/ˈkʌmkwɒt/ KUM-kwot), or cumquats in Australian English, are a group of small, angiosperm, fruit-bearing trees in the family Rutaceae. Their...

Agave (/əˈɡɑːvi/; also UK: /əˈɡeɪvi/; Anglo-Hispanic, also US: /əˈɡɑːveɪ/) is a genus of monocots native to the arid regions of the Americas. The genus...

Sequence homology is the biological homology between DNA, RNA, or protein sequences, defined in terms of shared ancestry in the evolutionary history of...

Eumetazoa (from Ancient Greek εὖ (eû) 'well', μετά (metá) 'after', and ζῷον (zôion) 'animal'), also known as diploblasts, Epitheliozoa or Histozoa, are...

Cloning is the process of producing individual organisms with identical genomes, either by natural or artificial means. In nature, some organisms produce...

Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus Gossypium in the mallow...

A feral cat or a stray cat is an unowned domestic cat (Felis catus) that lives outdoors and avoids human contact; it does not allow itself to be handled...

A barracuda is a large, predatory, ray-finned fish known for its fearsome appearance and ferocious behaviour. The barracuda is a saltwater fish of the...

The mung bean (Vigna radiata), alternatively known as green gram, mungo bean or mongo bean, is a plant species in the legume family. The mung bean is mainly...

A sex worker is a person who provides sex work, either on a regular or occasional basis. The term is used in reference to those who work in all areas of...

The golden hamster or Syrian hamster (Mesocricetus auratus) is a rodent belonging to the hamster subfamily, Cricetinae. Their natural geographical range...

The zucchini (/zuˈkiːni/ ; pl.: zucchini or zucchinis), courgette (/kʊərˈʒɛt/) or baby marrow (Cucurbita pepo) is a summer squash, a vining herbaceous...

African elephants are members of the genus Loxodonta comprising two living elephant species, the African bush elephant (L. africana) and the smaller African...

Natural history is a domain of inquiry involving organisms, including animals, fungi, and plants, in their natural environment, leaning more towards observational...

Drosophila melanogaster is a species of fly (an insect of the order Diptera) in the family Drosophilidae. The species is often referred to as the fruit...

Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as...

The quince (/ˈkwɪns/; Cydonia oblonga) is the sole member of the genus Cydonia in the Malinae subtribe (which also contains apples and pears, among other...

Buckwheat (Fagopyrum esculentum) or common buckwheat is a flowering plant in the knotweed family Polygonaceae cultivated for its grain-like seeds and as...

In botany, a drupe (or stone fruit) is an indehiscent type of fruit in which an outer fleshy part (exocarp, or skin, and mesocarp, or flesh) surrounds...

In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to it being stronger, faster or more dextrous...

Tapirs (/ˈteɪpər, ˈteɪpɪər, təˈpɪər/ TAY-pər, TAY-peer, tə-PEER) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in...

Ethology is a branch of zoology that studies the behaviour of non-human animals. It has its scientific roots in the work of Charles Darwin and of American...

The Columbian exchange, also known as the Columbian interchange, was the widespread transfer of plants, animals, precious metals, commodities, culture...

Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (1 August 1744 – 18 December 1829), often known simply as Lamarck (/ləˈmɑːrk/; French: [ʒɑ̃batist...

On the evening of 24 March 2020, the Government of India ordered a nationwide lockdown for 21 days, limiting the movement of the entire 1.38 billion (138...

A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. Land snail is the common name...

The Human Genome Project (HGP) was an international scientific research project with the goal of determining the base pairs that make up human DNA, and...

A plasmid is a small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently. They...

The nipple is a raised region of tissue on the surface of the breast from which, in females, milk leaves the breast through the lactiferous ducts to breastfeed...

The leopard cat (Prionailurus bengalensis) is a small wild cat native to continental South, Southeast, and East Asia. Since 2002 it has been listed as...

Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Due to their size, cytokines cannot cross the lipid...