Epithelium

Question 1

What’s the characteristic surface difference between epithelium and epithelioid tissues?

Answer 1

Epithelial tissue typically has a free surface, whereas epithelioid tissues resemble epithelium, but lack a free surface.

Question 2

True or False: Epithelial tissue is the most cellular tissue in the body?

Answer 2

True

Question 3

What epithelia classification does mesothelium fall under?

Answer 3

Simple Squamous Epithelium

Question 4

What molecular complexes tightly bind epithelium together?

Answer 4

Tight Junctions

Question 5

Name at least 1 epithelial tissue that is derived from ectoderm.

Answer 5

The skin epidermis and glands.

Question 6

The lining of the gastrointestinal tract (including glands) is derived from what, embryologically?

Answer 6

Endoderm

Question 7

Name at least two epithelial tissue examples that is derived from mesoderm.

Answer 7

The lining of the blood vessels, mesothelium, and the Bowman’s capsule.

Question 8

What is the most abundant collagen found in the basal lamina?

Answer 8

Type IV collagen.

Question 9

What type of proteins are found in the basal lamina that makes it PAS positive?

Answer 9

Glycoproteins

Question 10

Do lymph vessels and hepatic sinusoids have a basal lamina?

Answer 10

NO, they do not have a basal lamina.

Question 11

What two components make up a basement membrane?

Answer 11

Basal Lamina and Reticular Lamina

Question 12

What is the order of the reticular lamina, epithelium, basal lamina, and the connective tissue starting at the apical surface of the epithelial tissue?

Answer 12

Epithelium -> basal lamina -> reticular lamina -> connective tissue

Question 13

What 3 components make up the reticular lamina?

Answer 13

argyrophilic fibers, reticular fibers, and glycoproteins.

Question 14

Name two of the three major functions of the basement membrane.

Answer 14

1) Selective Filtration Barrier
2) Scaffold for embryogenesis and regeneration
3) Stabilization of tissue shapes

Question 15

Even through epithelial tissue does not have vessels, can it be innervated?

Answer 15

Yes, epithelial tissues may be innervated.

Question 16

Which layer of cells do you use to give the epithelial tissue its classification?

Answer 16

Superficial Layer

Question 17

Give two areas in the body where lightly keratinized stratified squamous epithelium could be found?

Answer 17

Esophagus and Vagina

Question 18

Is transitional epithelium a simple or stratified epithelium? Also, what about pseudostratified epithelium?

Answer 18

Simple, both transitional and pseudostratified epithelium are simple classification, NOT stratified.

Question 19

What are the 3 apical surface modifications that can be found on epithelial tissue?

Answer 19

Cilia, Stereocilia, and Microvilli

Question 20

What are the domains and features of a Polarized Cell?

Answer 20

• Apical Domain (with differentiations of cilia, microvilli, or stereocilia) and that domain must face a lumen or external environment
• Basolateral Domain
• Tight Junctions (intercelleular junctions)
• Basement Membrane

Question 21

Name 2 tubular structure lumina that simple squamous epithelium covers?

Answer 21

Ducts and Vessels (also other tubular structures too)

Question 22

Give some examples of where simple squamous epithelium is found?

Answer 22

• Walls of alveoli
• Bowman’s capsules
• Inner surfaces of membranous labyrinth and tympanic membrane

Question 23

Where is simple cuboidal epithelium found in the kidney? Also, what apical surface modifications can be found on it in the kidney? Does it always have this modification?

Answer 23

In the kidney tubules with a brush boarder (microvilli). No, does not always have a brush boarder.

Question 24

Give example of where simple cuboidal epithelium can be found in the body.

Answer 24

• surface of ovary
• pigmented epithelium of retina
• glands and ducts
• terminal bronchioles
• choroid plexus
• anterior capsule of lens of eye

Question 25

Where can simple ciliated columnar epithelium be found in the body?

Answer 25

* upper respiratory tract * uterine tubes * uterus * paranasal sinuses * central canal of the spinal cord

Question 26

Where is simple non-ciliated columnar epithelium found in the body?

Answer 26

* digestive tract beginning with the cardia of the stomach * gall bladder * in parts of the excretory ducts of glands

Question 27

What apical domain modification is sometimes found on simple columnar epithelium of intestinal cells?

Answer 27

Striated Border (microvilli)

Question 28

What kind of epithelium has a striated border and where is it located?

Answer 28

simple columnar and in the intestine

Question 29

What kind of epithelium has a brush border and where is it located?

Answer 29

simple cuboidal and in the kidney tubules

Question 30

Where is a few examples of where heavily keratinized stratified squamous is found?

Answer 30

Epidermis with connective tissue papillae | Cornea without connective tissue papillae

Question 31

Does heavily keratinized squamous epithelium in the cornea have connective tissue papillae?

Answer 31

No, only in the epidermis.

Question 32

What type of epithelium is found in the lining of the mouth, tongue, and part of the epiglottis?

Answer 32

lightly or non-keratinized squamous epithelium

Question 33

What type of epithelium can sometimes be found in small areas of the anal mucosa, large excretory ducts of some glands, and part of the male urethra?

Answer 33

STRATIFIED CUBOIDAL EPITHELIUM

Question 34

If stratified columnar epithelium were to be found, where would you expect to find it?

Answer 34

* ducts of adult sweat glands * fornix of the conjuctiva of the eye * parts of the male reproductive/urinary tract * pharynx * epiglottis

Question 35

What apical domain modifications can be found on pseudostratified epithelium in the epididymis?

Answer 35

stereocilia

Question 36

What structure in the body has ciliated pseudostratified columnar epithelium?

Answer 36

Trachea

Question 37

What are the 3 functions of epithelial tissues?

Answer 37

* protection (especially stratified squamous epithelium) * maintain concentration differences (tight barriers & leaky barriers) * secretion or absorption (typically simple or pseudostratified)

Question 38

Give two examples of epithelial tissue that has leaky barriers and then name the type of epithelium tissue these barriers would be found in.

Answer 38

*lining of gallbladder *proximal convoluted portion of renal tubule Would be found in simple columnar epithelium

Question 39

True of False: the height of the cell often reflects the level of secretory or absorptive activity of epithelial tissue.

Answer 39

True

Question 40

Does epithelium have vessels?

Answer 40

NO