ANAPHY - CHAPTER 4 TISSUE

TISSUES

TISSUES

are groups of specialized cells and the extracellular substances surrounding them

HISTOLOGY

is the microscopic study of tissue structure

EPITHELIUM

is found virtually everywhere, both inside and outside the body

EPITHELIUM

is primarily a cellular tissue, meaning there is very little extracellular material between the cells

EPITHELIUM

it forms the layers that cover the surfaces and line the hollow organs of our body

EPITHELIUM

it protects against foreign materials entering the body

FREE SURFACE

apical surface

FREE SURFACE

the surface that is exposed

BASAL SURFACE

the surface that is anchored in place

BASAL SURFACE

is held in place through attachment to a nonliving material that is somewhat like mortar for brick called basement membrane

BASEMENT MEMBRANE

is composed of specialized extracellular material secreted by the epithelial cells

BASEMENT MEMBRANE

it plays an important role in supporting and guiding cell migration during tissue repair

BASEMENT MEMBRANE

is typically porous, and regulates the movement of substances to and from the epithelial tissue above it

LATERAL SURFACE

where the epithelial cells are attached to each other

SIMPLE EPITHELIUM

consists of a single layer of cells, with each cell extending from the basement to the free surface

STRATIFIED EPITHELIUM

consists of more than one layer of cells, but only the deepest layer of cells attaches to the basement membrane

PSEUDOSTRATIFIED COLUMNAR EPITHELIUM

is a special type of simple epithelium

PSEUDOSTRATIFIED COLUMNAR EPITHELIUM

it consists of one layer of cells, with all the cells attached to the basement membrane

PSEUDOSTRATIFIED COLUMNAR EPITHELIUM

there appear to be two or more layers of cells because some of the cells are tall and extend to the free surface, whereas others are shorter and do not extend to the free surface

SQUAMOUS

cells are flat or scalelike

CUBOIDAL

(cubelike) cells are cube-shaped - about as wide as they are tall

COLUMNAR

(tall and thin, similar to a column) cells tend to be taller than they are wide

SIMPLE SQUAMOUS EPITHELIUM

is a single layer of thin, flat cells some substances can easily pass through this thin layer of cells, but others substances do not

SIMPLE CUBOIDAL EPITHELIUM

is a single layer cubelike cells carry out active transport, facilitated diffusion, or secretion

SIMPLE COLUMNAR EPITHELIUM

is a single layer of tall, thin cells the large size of these cells enables them to perform complex functions

PSEUDOSTRATIFIED COLUMNAR EPITHELIUM

is actually a single layer of cells, but the cells appear to be layered due to the differing heights of adjacent cells and positions of their nuclei provides protection for the body

STRATIFIED SQUAMOUS EPITHELIUM

forms a thick epithelium because it consists of several layers of cells the deepest cells are cuboidal or columnar and are capable of dividing and producing new cells — as these newly formed cells are pushed to the surface, they become flat and thin

TRANSITIONAL EPITHELIUM

is a special type of stratified epithelium that can stretch lines cavities that expand, such as the urinary bladder

SIMPLE SQUAMOUS EPITHELIUM

is best adapted for areas of the body where filtration and diffusion are common

SIMPLE SQUAMOUS EPITHELIUM

it protects organs in the pericardial, pleural, and peritoneal cavities by covering them with a thin, lubricated layer of tissue to allow organs to easily slide past each other without friction-induced damage occurring

SIMPLE CUBOIDAL EPITHELIUM

due to the larger volume of these cells, has a greater secretory capacity than simple squamous epithelium

SIMPLE CUBOIDAL EPITHELIUM

the larger size of cuboidal cells can create tubes that are sturdy and provide more protection than tubes composed of simple squamous epithelium

SIMPLE COLUMNAR EPITHELIUM

are much taller than those of cuboidal epithelium

SIMPLE COLUMNAR EPITHELIUM

of the small intestine produces digestive enzymes, absorb nutrients, and secretes mucus, which protects the lining of the intestine (because these cells are tall, bacteria cannot easily penetrate the lining of the intestine)

PSEUDOSTRATIFIED COLUMNAR EPITHELIUM

like simple columnar, is composed of tall cells and secrete mucus, which provides protection such as trapping inhaled debris in the trachea

STRATIFIED SQUAMOUS EPITHELIUM

forms a thick barrier, which can be as many as 3040 cells thick

KERATINIZED STRATIFIED SQUAMOUS EPITHELIUM

one type of stratified squamous epithelium forms the outer layer of the skin, contains the protein keratin

NONKERATINIZED STRATIFIED SQUAMOUS EPITHELIUM

such as is found in the mouth and throat, has a moist surface, but also provides protection against abrasion by acting as a mechanical barrier (however, water can move across this epithelium more readily than across the skin)

ENDOTHELIUM

tissue lining blood vessels (kind of tissue that is a specialized type of simple squamous epithelium)

DESMOSOMES

cell connection structures that mechanically bind epithelial cells together; most are found in epithelial tissues subjected to mechanical stress, such as the stratified squamous epithelium

HEMIDESMOSOMES

those that bind cells to the basement membrane; are the anchors of epithelial tissues to the underlying basement membrane, preventing the movement of the tissue

TIGHT JUNCTIONS

are cell connection structures that (1) form barriers to movement of molecules or ions between epithelial cells (2) anchor cells to each other

ADHESION BELTS

are found just below the tight junctions, and help the tight junctions anchor the epithelial cells to each other; provides additional strength for the bind of cells together at locations of tight junctions

GAP JUNCTIONS

cell connection structures that allow for intercellular communication consist of groups of channels that allow small molecules and ions to pass from one epithelial cell to an adjacent one

GLANDS

composed of epithelium supported by a network of connective tissue

ENDOCRINE GLANDS

produce chemicals called hormones; often termed ductless glands based on their structure

ENDOCRINE GLANDS

are associated with an extensive network of blood vessels, and their hormones are transported throughout the body by way of the blood

EXOCRINE GLANDS

produce a wide variety of products, such as saliva, sweat, and digestive tract secretions

EXOCRINE GLANDS

are primarily categorized on the basis of their structure, but they are also separated on the basis of their mode of secretion

DUCT

refers to the tube in contact with the epithelial tissue free surface, which transports the secreted material

SECRETORY PORTION OF THE GLAND

is found deeper in the epithelium and is composed of the cells responsible for producing the secreted material

UNICELLULAR

some exocrine glands are composed of only a single cell, such as goblet cells -secrete mucus

SIMPLE

are multicellular glands that have a single, non-branched duct

TUBULAR

is a straight, narrow tube the same width as the duct

ACINAR

a saclike structure those width is greater than the width of the duct

SIMPLE TUBULAR

glands forming a straight tube with no branching of the secretory portion

SIMPLE BRANCHED TUBULAR

gland with several tubular secretory portions branching from the single duct

SIMPLE ACINAR

glands with a single saclike secretory portion

SIMPLE BRANCHED ACINAR

glands with several acinar secretory portions branching from the single duct

COMPOUND TUBULAR

glands with multiple ducts, each with a narrow tubular secretory portion

COMPOUND ACINAR

glands with multiple ducts, each with several saclike secretory portions

COMPOUND TUBULOACINAR

glands with multiple ducts, each with several tubular and acinar secretory portions

MEROCRINE SECRETION

secretion is the release of secretory products through exocytosis and is the most common

APOCRINE SECRETION

secretion is the release of secretory products when a portion of the free surface of the epithelial cell pinches off, releasing cytoplasmic contents

HOLOCRINE SECRETION

secretion is the release of secretory products through shedding of entire cells

CONNECTIVE TISSUE

is a diverse primary tissue type that makes up part of every organ in the body

CONNECTIVE TISSUE

differs from the other three tissue types in that it consists of cells separated from each other by abundant extracellular matrix

TENDONS

are strong cables, or bands, of connective tissue that attach muscles to bone

LIGAMENTS

are connective tissue bands that hold bones together

BONES

provide rigid support for the body

SEMIRIGID CARTILAGE

supports structures, such as the nose, the ears, and the surface of joints

JOINTS

between bones allow one part of the body to move relative to other parts

ADIPOSE TISSUE

stores high-energy molecules (fat)

BONES

store minerals, such as calcium and phosphate

ADIPOSE TISSUE

cushions and protects the tissues it surrounds and provides an insulating layer beneath the skin that helps conserve heat

BLOOD

transports gases, nutrients, enzymes, hormones, and cells of the immune system throughout the body

CELLS OF THE IMMUNE SYSTEM AND BLOOD

provide protection against toxins and tissue injury, as well as against microorganisms

BONES

protect underlying structures from injury

BLAST

create the matrix

CYTES

maintain it

CLASTS

break it down for remodeling

MACROPHAGES

are large white blood cells that are capable of moving about and ingesting foreign substances, including microorganisms in the connective tissue

MAST CELLS

are nonmotile cells that release chemicals, such as histamine, that promote inflammation

COLLAGEN FIBERS

which resemble microscopic ropes, are very flexible but resist stretching

RETICULAR FIBERS

are very fine, short collagen fibers that branch to form a supporting network

ELASTIC FIBERS

have the ability to return to their original shape after being stretched or compressed, giving tissue an elastic quality

GROUND SUBSTANCE

consists of nonfibrous protein and other molecules it is the "shapeless" background against which the collagen fibers are seen through the microscope

PROTEOGLYCANS

are large molecules that consist of a protein core attached to many long polysaccharides

LOOSE CONNECTIVE TISSUE

consists of relatively few protein fibers that form a lacy network, with numerous spaces filled with ground substance and fluid

LOOSE CONNECTIVE TISSUE

it attaches the skin to underlying tissues and provides nourishment for the structures with which it is associated

AREOLAR

connective tissue primarily consists of collagen fibers and a few elastic fibers

ADIPOSE

consists of adipocytes - or fat cells, which contain large amounts of lipids for energy storage

ADIPOSE

composed of large cells and a small amount of extracellular matrix, which consists of loosely arranged collagen and reticular fibers with some scattered elastic fibers

ADIPOSE

also pads and protects parts of the body and acts as a thermal insulator

DENSE CONNECTIVE TISSUE

has a relatively large number of protein fibers that form thick bundles and fill nearby all of the extracellular space

DENSE COLLAGENOUS CONNECTIVE TISSUE

has an extracellular matrix consisting mostly of collagen fibers

DENSE ELASTIC CONNECTIVE TISSUE

has abundant elastic fibers among its collagen fibers

CARTILAGE

is composed of chondrocytes - cartilage cells, located in spaces called lacunae (small spaces) within an extensive matrix

CARTILAGE

is resilient because proteoglycans in the matrix trap water

HYALINE CARTILAGE

is the most abundant type of cartilage and has many functions; it covers the ends of bones where they come together to form joints