A&P_Lab[1] classification of tissues.txt

Groups of cells that are similar in structure and function

A part of the body formed of two or more tissues and adapted to carry out a specfic function

the study of tissues

covers surfaces; covers external body surface, lines it cavities and tubules, and generally marks off our insides from our outsides.

• polarity- membranes always have one free surface (apical surface), typically significally differenct from basal surface.
• cellularity and specialized contacts- cells fit closely together
• supported by connective tissues- adhesive basement membrane (basal lamina) connective tissue (reticular lamina)
• avascularity- no blood supply of their own, diffusion of nutrients from the underlying connective tissue
• regeneration-if well nurished, cells can reginerate themselves

• simple-one layer of cells attached to the basement membrane
• stratified-2 or more layers of cells

• squamous (scalelike)
• cuboidal (cubelike)
• columnar (column-shaped)

cells vary in height and the nuclei lie at different levels above the basement membrane, gives the false appearance of being stratified

stratified squamous epithelium of rounded or plump cells with the ability to slide over one another to allow the organ to be stretched-found in urinary systme subjected to periodic distention (bladder).

ductless glands, secrete hormones

retain their ducts, secretions empty through ducts, internal and external ...sweat and oil glands, liver, pancreas

• single layer of flattened cells with disc-shaped central nuclei and sparse cytoplasm- simplest of the epithelia
• function- allows passage of materials by diffusion and filtration in sites where protection is not important; secretes lubricating substances in serosae
• found in kidney glomeruli, air sacs of lungs, lining of heart, blood vessels, lymphatic vessels, lining of ventral body cavity (serosae)
• Cells touching cells-no space between cells

• single layer of cubelike cells with large spherical central nuclei
• function-secretion and absorption
• location-kidney tubules, ducts and secretory portions of small glands, ovary surface

• single layer of tall cells with round to oval nuclei, some cells bear cilia, layer may contain mucus-secreting unicellular glands (goblet cells)
• function-absorption and secretion of mucus, enzymes and other substances;ciliated type propels muicus by ciliary action
• location- nonciliated type lines most of the digestive tract (stomach to anal canal), gallbladder, and excretory ducts of some glands; ciliated variety lines small bronchi, uterine tubes and some regions of the uterus
• Goblet cells have mucus in them

• thick membrane composed of several cell layers-
• function-protects underlying tissues in areas subjected to abrasion
• location-nonkeratinized type forms the moist linings of the esophagus, mouth and vagina; keratinized variety forms the epidermis of the skin, a dry membrane

found in all parts of the body as discrete structures or as part of various body organs, the most abundant and widely distributed of the tissue types. functions- protect, support and bind together other tissues

protect and support other body tissues and organs

ligaments and tendons- bind the bones together or bind skeletal muscles to bones

soft packaging material that cushions and protects body organs

fat tissue provides insulation for the body tissues and a source of stored food

blood forming tissue replenishes the body's supply of red blood cells

• rich supply of blood vessesl (with some exceptions)
• composed of many types of cells
• great deal of noncellular, nonliving material (matirx) between the cells of connective tissue

nonliving material between the cells- distinguishes connective tissue from all other tissues-primarily responsible for strength associated with connective tissue

• component of matrix- composed chiefly of interstitial fluid, cell adhesion proteins and proteoglycans; liquid, semisolid, gel-like or very hard (glue)
• the fibers which provide support, include collagen (white), elastic (yellow), and reticular (fine collagen) - collagen fibers are most abundant

• gel-like matrix witha ll three fiber types; cells:fibroblasts, macrophages, mast cells, and some white blood cells
• function- wraps and cushions organs, plays important role in inflammation, holds and conveys tissue fluid
• location-widely distributed under epithelia of body; forms lamina propria of mucous membranes, packages organs, surrounds capillaries

• matrix as in areolar, but very sparse; closely packed adipocytes (fat) nucleus pushed to the sideby large fat droplet
• function- provides reserve fuel, insulates against heat loss, supports and protects organs
• locatations-under skin, around kidneys and eyeballs, within abdomen, in breasts

• primarily parallel collagen fibers, a few elastin fibers; major cell type is the fibroblast
• function- attaches muscles to bones or to muscles, attaches bones to bones, withstands great tensile stress when pulling force is applied in one direction
• locatation-tendons, most ligaments, aponeuroses

• primarily irregularly arranged collagen biers, some elastic fibers, major cell type is the fibroblast
• function-able to withstand tension exerted in many directions, provides structural strength
• location-dermis of the skin, submucosa of digestive tract, fibrous capsules of organs and joints

• amorphous but firm matrix; collagen fibers form an imperceptible network; chrondroblsts produce the matrix and when mature lie in lacunae
• function-support and reinforces has resilient cushioning properties, resists compressive stress
• location-forms most of the embryonic skeleton, covers the ends of long bones in joint cavities, forms costal cartilages of the ribs; cartilages of the nose, trachea and larynx

• similar to hyaline cartilage, but more elsastic fibers in matrix
• function-maintains the shape of a structure while allowing great flexibility
• location-supports the external ear, epiglottis

• matrix similar to but less firm than that in hyaline cartilage, thick collagen fibers predominate
• function-tensile stenght with the ability to absorb compressive shock
• location-intervertebral discs, pubic symphysis, discs of knee joint

large, darkly staining granules in its cytoplasm

• 2 major cell populations-
• neuroglia-special supporting cells that protect support and insulate themore delicate neurons
• neurons- highly specialized to receive stimuli, and to conduct waves of excitation, or impulses to all parts fot the body

highly specialized to contract and produce most types of body movement

the meat or flesh, attached to the skeleton

found only in the heart, involuntary muscle control

also called visceral muscle, found mainly in the walls of hollow organs- no striations are visible the uninucleate smooth muscle cells are spindle shaped