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Level 3 Anatomy & Physiology Training Manual MODULE 1

Page 1

Level 3

Anatomy & Physiology Training Manual

SUPPORTING YOUR DREAMS & YOUR CAREER

www.vanityfairschoolofbeauty.co.uk @vanityfairschoolofbeauty


MODule 1 CELLS, TISSUES & MEMBRANE

SUPPORTING YOUR DREAMS & YOUR CAREER

www.vanityfairschoolofbeauty.co.uk @vanityfairschoolofbeauty


CELL STRUCTURE Cells have many parts, each with a different function. Cells are the basic building blocks of all living things. The human body is composed of trillions of cells. They provide structure for the body, take in nutrients from food, convert those nutrients into energy, and carry out specialized functions. Cells also contain the body’s hereditary material and can make copies of themselves.

A cell consists of three parts: the cell membrane, the nucleus, and, between the two, the cytoplasm. Within the cytoplasm lie intricate arrangements of fine fibers and hundreds or even thousands of miniscule but distinct structures called organelles. of these parts, called organelles, are specialized structures that perform certain tasks within the cell. Human cells contain the following major parts, listed in alphabetical order: Cytoplasm Within cells, the cytoplasm is made up of a jelly-like fluid (called the cytosol) and other structures that surround the nucleus. Cytoskeleton The cytoskeleton is a network of long fibers that make up the cell’s structural framework. The cytoskeleton has several critical functions, including determining cell shape, participating in cell division, and allowing cells to move. It also provides a track-like system that directs the movement of organelles and other substances within cells. Endoplasmic reticulum (ER) This organelle helps process molecules created by the cell. The endoplasmic reticulumalso transports these molecules to their specific destinations either inside or outside the cell. Golgi apparatus The Golgi apparatus packages molecules processed by the endoplasmic reticulum to be transported out of the cell. Lysosomes and peroxisomes These organelles are the recycling center of the cell. They digest foreign bacteria that invade the cell, rid the cell of toxic substances, and recycle worn-out cell components. Mitochondria Mitochondria are complex organelles that convert energy from food into a form that the cell can use. They have their own genetic material, separate from the DNA in the nucleus, and can make copies of themselves.


Nucleus The nucleus serves as the cell’s command center, sending directions to the cell to grow, mature, divide, or die. It also houses DNA (deoxyribonucleic acid), the cell’s hereditary material. The nucleus is surrounded by a membrane called the nuclear envelope, which protects the DNA and separates the nucleus from the rest of the cell. Plasma membrane The plasma membrane is the outer lining of the cell. It separates the cell from its environment and allows materials to enter and leave the cell. Ribosomes Ribosomes are organelles that process the cell’s genetic instructions to create proteins. These organelles can float freely in the cytoplasm or be connected to the endoplasmic reticulum.


CEL FUNCTIONS Cels have multpiple functions to carry out in order to survive.

CELL RESPIRATION carry out the process of metabolism every cell requires oxygen. The cells semi-permeable membrane absorbs oxygen when it is used to oxidise nutirnents to provide energy and heat. Cell respiration produces waste products, including carbon dioxide and water is passed out through the semi-premeable membrane.

CELL GROWTH are able to grow until they are ready to produce. A cell is able to both grow and repair itself, as it can manufacture proteins.

CELL WASTE

produces a variety of waste material, which is removed from the cell through the

semi-permeable membrane.

MOVEMENT WITHIN THE CELL is possible within the whole or part of the cell white blood cells can move freely within the cell.

CELL STIMULUS AND IRRITABILITY cell can respond to a chemical, thermal or physical stimulus. As an example when stimulated by a nerve cell a muscle fibre contacts.

CELL REPRODUCTION

growth is complete, cell divison occurs through a process called mitosis.


MOVEMENT OF SUBSTANCES ACROSS THE MEMBRANE The survival of the cell depends on maintaining the difference between extracellular and intracellular material. Mechanisms of movement across the cell membrane include simple diffusion, osmosis, filtration, active transport, endocytosis, and exocytosis. Simple diffusion is the movement of particles (solutes) from a region of higher solute concentration to a region of lower solute concentration. Osmosis is the diffusion of solvent or water molecules through a selectively permeable membrane. Filtration utilizes pressure to push substances through a membrane. Active transport moves substances against a concentration gradient from a region of lower concentration to a region of higher concentration. It requires a carrier molecule and uses energy. Endocytosis refers to the formation of vesicles to transfer particles and droplets from outside to inside the cell. Secretory vesicles are moved from the inside to the outside of the cell by exocytosis.

CELL DIVISION Cell division is the process by which new cells are formed for growth, repair, and replacement in the body. This process includes division of the nuclear material and division of the cytoplasm. All cells in the body (somatic cells), except those that give rise to the eggs and sperm (gametes), reproduce by mitosis. Egg and sperm cells are produced by a special type of nuclear division called meiosis in which the number of chromosomes is halved. Division of the cytoplasm is called cytokinesis. Somatic cells reproduce by mitosis, which results in two cells identical to the one parent cell. Interphase is the period between successive cell divisions. It is the longest part of the cell cycle. The successive stages of mitosis are prophase, metaphase, anaphase, and telophase. Cytokinesis, division of the cytoplasm, occurs during telophase.


MITOSIS Mitosis is a special type of cell division that occurs in the production of the gametes, or eggs and sperm. These cells have only 23 chromosomes, one-half the number found in somatic cells, so that when fertilization takes place the resulting cell will again have 46 chromosomes, 23 from the egg and 23 from the sperm.

DNA REPLICATION AND PROTEIN SYNTHESIS Proteins that are synthesized in the cytoplasm function as structural materials, enzymes that regulate chemical reactions, hormones, and other vital substances. DNA in the nucleus directs protein synthesis in the cytoplasm. A gene is the portion of a DNA molecule that controls the synthesis of one specific protein molecule. Messenger RNA carries the genetic information from the DNA in the nucleus to the sites of protein synthesis in the cytoplasm.


TISSUES Tissue is a group of cells that have similar structure and that function together as a unit. A nonliving material, called the intercellular matrix, fills the spaces between the cells. This may be abundant in some tissues and minimal in others. The intercellular matrix may contain special substances such as salts and fibers that are unique to a specific tissue and gives that tissue distinctive characteristics. There are four main tissue types in the body: designed for specific functions.

epithelial, connective, muscle, and nervous. Each is


EPITHELIAL TISSUE Provides protective layer for internal and external body surfaces. Epithelial tissues are widespread throughout the body. They form the covering of all body surfaces, line body cavities and hollow organs, and are the major tissue in glands. They perform a variety of functions that include protection, secretion, absorption, excretion, filtration, diffusion, and sensory reception. The cells in epithelial tissue are tightly packed together with very little intercellular matrix. Because the tissues form coverings and linings, the cells have one free surface that is not in contact with other cells. Opposite the free surface, the cells are attached to underlying connective tissue by a non-cellular basement membrane. This membrane is a mixture of carbohydrates and proteins secreted by the epithelial and connective tissue cells. Epithelial cells may be squamous, cuboidal, or columnar in shape and may be arranged in single or multiple layers.


CONNECTIVE TISSUE Connective tissues bind structures together, form a framework and support for organs and the body as a whole, store fat, transport substances, protect against disease, and help repair tissue damage. They occur throughout the body. Connective tissues are characterized by an abundance of intercellular matrix with relatively few cells. Connective tissue cells are able to reproduce but not as rapidly as epithelial cells. Most connective tissues have a good blood supply but some do not.

Numerous cell types are found in connective tissue. Three of the most common are the fibroblast, macrophage, and mast cell. The types of connective tissue include loose connective tissue, adiposetissue, dense fibrous connective tissue, elastic connective tissue, cartilage, osseous tissue (bone), and blood.


MUSCLE TISSUE Muscle tissue is what gives us movement and is composed of cells that have the special ability to shorten or contract in order to produce movement of the body parts. The tissue is highly cellular and is well supplied with bloodvessels. The cells are long and slender so they are sometimes called muscle fibers, and these are usually arranged in bundles or layers that are surrounded by connective tissue. Actin and myosin are contractile proteins in muscle tissue. Muscle tissue can be categorized into skeletal muscle tissue, smooth muscle tissue, and cardiac muscle tissue.

Skeletal muscle fibers are cylindrical, multinucleated, striated, and under voluntary control. Smooth muscle cells are spindle shaped, have a single, centrally located nucleus, and lack striations. They are called involuntary muscles. Cardiac muscle has branching fibers, one nucleus per cell, striations, and intercalated disks. Its contraction is not under voluntary control.

NERVOUS TISSUE Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities. It stimulates muscle contraction, creates an awareness of the environment, and plays a major role in emotions, memory, and reasoning. To do all these things, cells in nervous tissue need to be able to communicate with each other by way of electrical nerveimpulses. The cells in nervous tissue that generate and conduct impulses are called neurons or nerve cells.

These cells have three principal parts:

the dendrites, the cell body, and one axon. The main part

of the cell, the part that carries on the general functions, is the cell body. Dendrites are extensions, or processes, of the cytoplasm that carry impulses to the cell body. An extension or process called an axon carries impulses away from the cell body. Nervous tissue also includes cells that do not transmit impulses, but instead support the activities of the neurons. These are the glial cells (neuroglial cells), together termed the neuroglia. Supporting, or glia, cells bind neurons together and insulate the neurons. Some are phagocytic and protect against bacterial invasion, while others provide nutrients by binding blood vessels to the neurons.


MEMBRANE

Body membranes are thin sheets of tissue that cover the body, line body cavities, and cover organs within the cavities in hollow organs. They can be categorized into epithelial and connective tissuemembrane.

Epithelial membranes consist of epithelial tissue and the connective tissue to which it is attached. The two main types of epithelial membranes are the mucous membranes and serous membranes.

Mucous membranes are epithelial membranes that consist of epithelial tissue that is attached to an underlying loose connective tissue. These membranes, sometimes called mucosae, line the body cavities that open to the outside. The entire digestive tract is lined with mucous membranes. Other examples include the respiratory, excretory, and reproductive tracts.

Serous membranes line body cavities that do not open directly to the outside, and they cover the organs located in those cavities. Serous membranes are covered by a thin layer of serous fluid that is secreted by the epithelium. Serous fluid lubricates the membrane and reduces friction and abrasion when organs in the thoracic or abdominopelvic cavity move against each other or the cavity wall. Serous membranes have special names given according to their location. For example, the serous membrane that lines the thoracic cavity and covers the lungs is called pleura.

Connective tissue membranes contain only connective tissue. Synovial membranes and meninges belong to this category.

Synovial membranes are connective tissue membranes that line the cavities of the freely movable joints such as the shoulder, elbow, and knee. Like serous membranes, they line cavities that do not open to the outside. Unlike serous membranes, they do not have a layer of epithelium. Synovial membranes secrete synovial fluid into the joint cavity, and this lubricates the cartilage on the ends of the bones so that they can move freely and without friction.

Meninges the connective tissue covering on the brain and spinal cord, within the dorsal cavity, are called meninges. They provide protection for these vital structures.


REVIEW OF CELLS TISSUES & MEMBRANES Here is what we have learned from Cells, Tissues, and Membranes: A cell consists of three parts: the cell membrane, the nucleus, and between the two, the cytoplasm. The cell nucleus contains genetic material and regulates activities of the cell. It determines how the cell will function, as well as the basic structure of that cell. All of the functions for cell expansion, growth and replication are carried out in the cytoplasm of a cell. Tissue is a group of cells that have similar structure and that function together as a unit. Primary types of body tissues include epithelial, connective, muscular, and nervous tissues. Epithelial tissues form the covering of all body surfaces, line body cavities and hollow organs, and are the major tissue in glands. Connective tissues bind structures together, form a framework and support for organs and the body as a whole, store fat, transport substances, protect against disease, and help repair tissue damage. Muscle tissue is composed of cells that have the special ability to shorten or contract in order to produce movement of body parts. Nervous tissue is responsible for coordinating and controlling many body activities. Body membranes are thin sheets of tissue that cover the body, line body cavities, and cover organs within the cavities in hollow organs. Two main categories of body membranes are epithelial and connective tissue membranes. Sub-categories include mucous membranes, serous membranes, synovial membranes, and meninges.


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