Epithelial Tissue (Test #1)

Question 1

Epithelial Tissue

Answer 1

Covers a body surface or lines a body cavity
-most glands
-functions:
protection, diffusion, absorbtion, secretion, and ion transport, filteration, forms slippery surfaces

Question 2

Cellularity

Answer 2

*SC of ET

cells separated by minimal extracellular material (closely adjacent)

Question 3

Specialized Contacts

Answer 3

*SC of ET

Cells joined by special junctions

Question 4

Polarity

Answer 4

*SC of ET
cell regions of the apical surface differ from the basal surface
-intestinal ep., the apical surface faces the inside of the gut

Question 5

Avascular but Innervated

Answer 5

• SC of ET
• no blood supply (blister)
• epithelia receive nutrients from underlying connective tissue

Question 6

Regeneration

Answer 6

-Lost cells quickly replaced by cell division

Question 7

Classifications of Epithelia

Answer 7

Simple
Stratified
Squamous
Cuboidal
Columnar

Question 8

Simple Squamous

Answer 8

single layer, most simple
allows passage of materials by diffusion and filteration in sites where protection is not important
air sacs of lungs, lining of ventral body cavity, lining of <3 and blood vessels

Question 9

Simple Cuboidal

Answer 9

single layer of cubelike cells with large, spherical central nuclei
secretion and absorbtion
kidney tubules, ducts and secretory portions of small glands, ovary surface

Question 10

Simple Columnar

Answer 10

single layer, tall, bear cilia, may contain mucus glands
absorption, secretion of mucus, enzymes, and other substances
nonciliated type lines most of digestive tract, gallbladder, and excretory ducts of some glands; ciliated variety lines small bronchi, and some regions of uterus

Question 11

Pseudostratified Ciliated Columnar

Answer 11

single layer of cells of differing heights, some not reaching free surface, looks as though they are stacked ontop of eachother but are not
secretion, particularly of mucus
nonciliated type in males sperm carrying ducts and ducts of large glands, ciliated lined the trachea, most of upper respiratory tract

Question 12

Stratified Squamous

Answer 12

thick membrane composed of several cell layers; in keratinized type, the surface cells are full of keratin and dead; basal cells are active in mitosis and produce the cells of the more superficial layers
protects underlying tissues in areas subjected to abrasion(friction)
nonkeratinized type forms the moist linings of the esophagus, moouth, and vagina, keratinized variety forms the epidermis of the skin, a dry membrane

Question 13

Transitional Epithelium

Answer 13

resembles both stratified squamous and stratified cuboidal; basal cells cuboidal or columnar; surface cells dome shaped or squamous like
Stretches readily and permits distension of urinary organ contained urine
lines the uterus, bladder, and urethra (purple)