TISSUES

Question 1

Four Basic Tissue Types

Answer 1

Epithelial
Connective
Muscular
Nervous

Question 2

cells producing very abundant ECM

Answer 2

Connective

Question 3

composed of elongated cells specialized for contraction and movement

Answer 3

Muscular

Question 4

cells with long, fine processes specialized to receive, generate, and transmit nerve impulses

Answer 4

Nervous

Question 5

cells responsible for the organ’s specialized functions

Answer 5

PARENCHYMA

Question 6

cells of which have a supporting role in the organ, always made up of connective tissue (except in brain and spinal cord)

Answer 6

STROMA

Question 7

line all external and internal surfaces of the body.

All substances that enter or leave an organ must cross this type of tissue.

composed of closely aggregated polyhedral cells adhering strongly to one another and to a thin layer of ECM

forms cellular sheets that line the cavities of organs and coyer the body surface

Answer 7

EPITHELIAL TISSUE

Question 8

PRINCIPAL FUNCTIONS OF EPITHELIAL

Answer 8

Covering, lining, and protecting surfaces (eg, epidermis)

Absorption (eg, the intestinal lining)

Secretion (eg, parenchymal cells of glands)

Question 9

generally have elongated nuclei,

Answer 9

Columnar cells

Question 10

have flattened nuclei,

Answer 10

Squamous cells

Question 11

have more spherical nuclei

Answer 11

cuboidal or pyramidal cells

Question 12

The basal surface of all epithelia rests on a thin extracellular, felt-like sheet of macromolecules referred to as the ___

a semipermeable filter for substances reaching epithelial cells from below.

Answer 12

BASEMENT MEMBRANES

Question 13

Nearest the epithelial cells
Thin, electron-dense, sheet-like layer of fine fibrils

Answer 13

BASAL LAMINA

Question 14

Beneath the basal lamina
More diffuse and fibrous

Answer 14

RETICULAR LAMINA

Question 15

self-assemble into a two- dimensional network of evenly spaced subunits resembling the mesh of a window screen,

Answer 15

Type IV collagen

Question 16

: These are large glycoproteins that attach to transmembrane integrin proteins in the basal cell membrane and project through the mesh ,formed by the type IV collagen

Answer 16

Laminin

Question 17

a short, rod-like protein and a proteoglycan, both of these cross-link laminins to the type IV collagen network, helping to provide the basal lamina’s three-dimensional structure. to bind the epithelium to that structure, and to determine its porosity and the size of molecules able to filter through it.

Answer 17

Nidogen and perlecan

Question 18

contains type III collagen and is bound to the basal lamina by anchoring fibrils of type Vil collagen, both of which are produced by cells of the connective tissue

Answer 18

RETICULAR LAMINA

Question 19

SPECIALIZATIONS OF THE APICAL CELL SURFACE

Answer 19

MICROVILLI
STEREOCILIA
CILIA

Question 20

In epithelia specialized for absorption. L. villus, tuft), usually of uniform length.

• In cells such as those lining the small intestine, densely packed __ are visible as a brush or striated border projecting into the lumen.

Answer 20

microvilli

Question 21

• Much less common type of apical process, best seen on the absorptive epithelial cells lining the male reproductive system.
• Increases the cells’ surface area, facilitating absorption.
• __ are typically much longer and less motile than microvilli, and may show branching distally.

Answer 21

Stereocilia

Question 22

are long, highly motile apical structures, larger than microvilli and containing internal arrays of microtubules.

exhibit rapid beating patterns that move a current of fluid and suspended matter in one direction along the epithelium.

Answer 22

Cilia

Question 23

most (if not all) other cell types have at least one short projection called a___, which is not motile but is enriched with receptors and signal transduction complexes for detection of light, odors, motion, and flow of liquid past the cell

Answer 23

primary cilium

Question 24

TYPES OF EPITHELIA

Answer 24

Covering (or lining) epithelia

Secretory (glandular) epithelia

Question 25

Organized into one or more layers that cover the surface or line the cavities of an organ * Classified according to the number of cell layers and the cell morphology in the outer layer.

Answer 25

COVERING (LINING) EPITHELIA

Question 26

contain one cell layer

Answer 26

Simple epithelia

Question 27

contain two or more layers.

Answer 27

stratified epithelia

Question 28

Based on cell shape, simple epithelia are further classified as

Answer 28

squamous cuboidal columnar

Question 29

thin cells

Answer 29

squamous

Question 30

(cell width and thickness roughly similar),

Answer 30

cuboidal

Question 31

(cells taller than they are wide).

Answer 31

columnar

Question 32

The very thin surface cells of ___ can be "keratinized" (packed with keratin filaments) or "nonkeratinized" (with relatively sparse keratin).

Answer 32

STRATIFIED SQUAMOUS EPITHELIUM

Question 33

Lining of vessels (endothelium); serous lining of cavities: pericardium,pleura, peritoneum, (mesothelium)

Answer 33

simple squamous

Question 34

Facilitates the movement of the viscera (mesothelium), active transport by pinocytosis (mesothelium & endothelium), secretion of biological active molecules (mesothelium)

Answer 34

simple squamous

Question 35

Covering the ovary, thyroid

Answer 35

simple cuboidal

Question 36

covering, secretion

Answer 36

simple cuboidal

Question 37

Lining of intestine, gallbladder

Answer 37

simple columnar

Question 38

Protection, lubrication, absorption, secretion

Answer 38

simple columnar

Question 39

Epidermis FUNCTION: Protection; prevents water loss

Answer 39

Stratified Squamous Keratinized

Question 40

Mouth, esophagus, larynx, vagina, and canal FUNCTION: Protection, secretion; prevents water loss

Answer 40

Stratified Squamous nonkeratinized

Question 41

Sweat glands, developing ovarian follicles FUNCTION: Protection, secretion

Answer 41

Stratified cuboidal

Question 42

Ladder, ureters, renal calyces FUNCTION: Protection, distensibility

Answer 42

Stratified TRansitional

Question 43

Conjunctiva FUNCTION: protection

Answer 43

Stratified Columnar

Question 44

Lining of trachea, bronchi, nasal cavity FUNCTION: Protection, secretion, cilia-mediated transport of particles trapped in mucus out of the air passages

Answer 44

Pseudostratified

Question 45

(layers of cells with nuclei at different levels; not all cells reach surface but all adhere to basal lamina)

Answer 45

Pseudostratified

Question 46

*is found mainly in the epidermis of skin, where it helps prevent dehydration from the tissue). * Its cells form many layers, with the less differentiated cuboidal cells near the basement membrane. * These cells become more irregular in shape and then flatten as they accumulate keratin in the process of keratinization and, are moved progressively toward the skin surface, where they become thin, metabolically inactive packets (squames) of keratin lacking nuclei.

Answer 46

STRATIFIED SQUAMOUS KERATINIZED EPITHELIUM

Question 47

lines moist internal cavities (eg, mouth, esophagus, and vagina) where water loss is not a problem. Here the flattened cells of the surface layer retain their nuclei and most metabolic functions.

Answer 47

Stratified squamous nonkeratinized epithelium

Question 48

occurs in the excretory ducts of salivary and sweat glands.

Answer 48

Stratified cuboidal epithelium

Question 49

is seen in the conjunctiva lining the eyelids, where it is both protective and mucus secreting

Answer 49

Stratified columnar epithelium

Question 50

lines much of the urinary tract, extending from the kidneys to the proximal part of the urethra, and is characterized by a superficial layer of large, dome-like cells sometimes called umbrella cells.

Answer 50

Urothelium

Question 51

Tall, irregular cells all are attached to the basement membrane. . Their nuclei are at different levels and not all cells extend to the free surface, giving a stratified appearance. * Example: lining of the upper respiratory tract

Answer 51

PSEUDOSTRATIFIED COLUMNAR EPITHELIUM

Question 52

function mainly to produce and secrete various macromolecules may occur in epithelia with other major functions or comprise specialized organs called glands. * may synthesize, store, and release proteins (eg, in the pancreas), lipids (eg, adrenal, sebaceous glands), or complexes of carbohydrates and proteins (eg, salivary glands).

Answer 52

SECRETORY EPITHELIA & GLANDS

Question 53

abundant in the lining of the small intestine and respiratory tract, which secretes lubricating mucus that aids the function of these organs

Answer 53

Goblet cell

Question 54

remain connected with the surface epithelium, the connection forming the tubular ducts lined with epithelium that deliver the secreted material where it is used.

Answer 54

Exocrine glands

Question 55

lack ducts. Thin-walled blood vessels (capillaries) adjacent to endocrine cells absorb their secreted hormone products for transport in blood to target cells throughout the body

Answer 55

Endocrine glands

Question 56

Glands can be:

Answer 56

Simple Compound

Question 57

Secretory portions can be ___, ___

Answer 57

Secretory portions can be tubular (either short or long and coiled) or acinar (rounded and saclike):

Question 58

TYPES OF SECRETION

Answer 58

Merocrine Holocrine Apocrine

Question 59

This is the most common method of protein or glycoprotein secretion and involves typical exocytosis from membrane-bound vesicles or secretory granules.

Answer 59

Merocrine secretion

Question 60

Here cells accumulate product continuously as they enlarge and underga terminal differentiation, culminating in complete cell disruption that releases the product and cell debris into the gland's lumen. This is best seen in the sebaceous glands producing lipidrich material in skin.

Answer 60

Holocrine secretion

Question 61

Here product accumulates at the cells apical ends, portions of which are then extruded to release the product together with small amounts of cytoplasm and cell membrane, Lipid droplets are secreted in the mammary gland in this manner

Answer 61

Apocrine secretion:

Question 62

are key sites for ion and water transport, maintaining the body's overall balance of salts and water.

Answer 62

Epithelia of kidney tubules