Histology - Epithelial Tissue (A2)

Question 1

Name the 4 basic tissue types

Answer 1

epithelial
muscle
connective
nervous
(E=MC^N)

Question 2

Epithelial tissue is composed of cells that…

Answer 2

line the cavities and surfaces of structures throughout the body.

Question 3

Name the three general shapes of epithelial tissue.

Answer 3

squamous
cuboidal
columnar

Question 4

define squamous

Answer 4

“squashed”, scaly or flattened (nucleus looks like a flattened disc)

Question 5

define cuboidal

Answer 5

cells are relative equal height and width (nucleus is spherical and located in the center of the cell)

Question 6

define columnar

Answer 6

cells are taller than they are wide (nucleus is oval of “egg-shaped” usually oriented lengthwise and in the basal/bottom region of the cell)

Question 7

what type of cell layers are epithelial tissues generally found in?

Answer 7

simple
stratified
pseudostratified

Question 8

define simple cell layers

Answer 8

one cell layer thick, all cells contact basement membrane

Question 9

define stratified cell layers

Answer 9

two or more layers, only the deepest layer is in contact with the basement membrane

Question 10

define pseudostratified cell layers

Answer 10

appears layered because the nuclei are distributed at different levels, but all cells are in contact with basement membrane

Question 11

name the steps to identifying epithelium tissues

Answer 11

1. determine how many cell layers there are:
   - if only one layer on a basement membrane, it’s simple
   - if more than one layer , it’s stratified
2. determine the epithelial cell shapes by looking at the cells nearest the apical surface

Question 12

define apical surface

Answer 12

the surface of the cell not attached to the basement membrane

Question 13

describe structure of simple squamous epithelial tissue

Answer 13

one layer of flattened cells

Question 14

describe structure of simple cuboidal epithelial tissues

Answer 14

one layer of cells about as tall as they are wide

Question 15

describe structure of simple columnar, nonciliated epithelial tissue

Answer 15

one layer of nonciliated cells that are taller than they are wide; oval nucleus in nasal region; often contains microvilli (fuzzy structure known as brush border) and goblet cells

Question 16

define nonciliated

Answer 16

not having cilia

Question 17

simple columnar, ciliated

Answer 17

one layer of ciliated cells that are taller than they are wide

Question 18

define ciliated

Answer 18

with cilia

Question 19

stratified squamous, keratinized

Answer 19

many layers thick; cells in surface layer are dead and filled with the protein keratin; no nuclei!

basal (vase/bottom) cells appear cuboidal, apical cells appear squashed/squamous

Question 20

define keratinized

Answer 20

becoming a form of keratin/protein

Question 21

stratified squamous, nonkeratinized

Answer 21

many layers thick; no keratin in cells; surface layers are alive, flat, and moist.

Question 22

define nonkeratinized

Answer 22

no dead parts, no proteins

Question 23

describe structure of stratified cuboidal epithelial tissue

Answer 23

two or more layers of cells; apical layer of cells is cuboidal shaped

Question 24

describe structure of stratified columnar epithelial cells

Answer 24

two or more layers of cells; cells are taller than they are wide

Question 25

describe structure of pseudostratified columnar epithelial tissue

Answer 25

one layer of cells of varying heights; all cells attached to basement membrane; both ciliated and nonciliated/with or without cilia and goblet cells

Question 26

describe structure of transitional epithelial tissues

Answer 26

structure varies but it’s multiple layers that are either “stretched” or “relaxed”

Question 27

function and location of simple squamous epithelial tissue cells

hint: extremely delicate and found only in protected regions where moist surfaces reduce friction and abrasion

Answer 27

function: rapid diffusion, filtration, and some secretion
location: air sacs in lungs (alveoli), lining lumen of blood cells (endothelium), serous membranes of body cavities (mesothelium)

Question 28

function and location of stratified squamous epithelial tissue cells

Answer 28

function: protection of underlying tissue
location: keratinized- epidermis of skin, nonkeratinized- lining of vagina, oral cavity, esophagus and anus

Question 29

function and location of simple cuboidal epithelial tissue cells
hint: they look like rows of pancakes in the textbook figures

Answer 29

function: primarily absorption and secretion
location: covers the surface of the ovaries and lines thyroid gland follicles, forms the walls of kidneys, forms ducts and secretory regions of exocrine glands

Question 30

function and location of stratified cuboidal epithelial tissue cells

Answer 30

function: mainly protective, strengthens the wall of gland ducts and secretion
location: large ducts in most exocrine glands (sweat, male urethra)

Question 31

function and location of simple columnar epithelial tissue cells

Answer 31

function: active movement of molecules occurs across this type of epithelium by either absorption or secretion
location: nonciliated- lines most of the digestive tract (from stomach to anal canal), ciliated- lines internal surface of uterine tubes, present in bronchioles of lungs

Question 32

function and location of nonciliated simple columnar epithelial tissue cells

Answer 32

function: absorption and secretion
location: lines most of the digestive tract

Question 33

function and location of ciliated simple columnar epithelial tissue cells

Answer 33

function: secretion of mucin; oocyte movement through uterine tube
location: lines the internal surface of uterine tubes; bronchioles of the lung

Question 34

structure and function of stratified columnar epithelial tissue cells

Answer 34

function: protection and secretion
location: relatively rare but are in exocrine glands and segments of the male urethra

Question 35

structure and function of pseudostratified columnar epithelial tissue cells

Answer 35

function: protection. (also- ciliated have goblet cells and are involved with secretion of mucin but nonciliated do not)
location: ciliated-lines most of the respiratory tract, nonciliated- rare, lines the epididymis and part of male urethra

Question 36

function and location of transitional epithelial tissue cells

Answer 36

function: distinction and relaxation to accommodate urine volume changes in the bladder, ureters, and urethra (permits stretching)
location: lining of urinary bladder, ureters, and proximal part of the urethra