Histology Lecture 4: Characteristics of Epithelial Tissues I

Question 1

What is the material that lies outside of cells and plays a support role in holding the cells together

Answer 1

matrix

Question 2

resemble epithelial tissues but lack exposure to a lumen

Answer 2

epithelioid tissue

Question 3

surfaces of the cell that are in contact with the lumen

Answer 3

apical domain

Question 4

include the surfaces of cells that are locked together by
special junctional complexes with neighboring cells as well as the surface opposite the apical domain that is in contact with the basal lamina

Answer 4

basolateral domain

Question 5

two parts of the basement membrane

Answer 5

basal lamina and reticular lamina

Question 6

next to the epithelial layer and is 50-80 nm
thick. It is composed of type IV collagen plus glycoproteins and is PAS+. It is absent in lymph vessels and hepatic sinusoids as these structures are designed to be leaky.

Answer 6

Basal Lamina

Question 7

is in contact with underlying connective tissue and consists of argyrophilic (“silver loving”) fibers, reticular fibers and glycoproteins

Answer 7

Reticular Lamina

Question 8

Functions of the Basement Membrane

Answer 8

1) Selective filtration barrier; 2) Scaffold for embyrogenesis and regeneration; 3) Stabilization of tissue shapes

Question 9

This epithelium appears to be stratified, but all cells are in contact with the basal lamina, so it is technically a simple epithelium. The appearance of stratification is due to the variable positions of the nuclei within the cells

Answer 9

pseudostratified epithelium

Question 10

This is thought to be a type of simple epithelium but with the appearance of having more than one layer because of the positions of the nuclei. All cells are in contact with the basal lamina, but the dome-shaped surface cells give the appearance of stratified epithelium. This category of epithelium is associated with the urinary track and may
be referred to as urothelium

Answer 10

Transitional Epithelium

Question 11

Characterized by surface modifications such as cilia or microvilli and face a lumen or external environment

Answer 11

apical domains

Question 12

The sides and bases of the cells are characterized by intercellular junctions. These cell surfaces are in contact with the basement membrane and surrounding cells/

Answer 12

Basolateral domains

Question 13

a microtubular structure that forms the basic structure of the cilium

Answer 13

axoneme

Question 14

contains nine triplet microtubules in a helicoid array without a central microtubular component

Answer 14

basal body

Question 15

consists of an axoneme formed by a central pair of microtubules surrounded by nine concentrically arranged microtubular pairs. This assembly is known as the 9 + 2 microtubular doublet arrangement

Answer 15

cilium

Question 16

finger-like cell projections of the apical epithelial cell surface containing a core of crosslinked microfilaments (a
polymer of G-actin monomers).

Answer 16

microvilli

Question 17

formed by microvilli and typically indicate an absorptive function of the cells

Answer 17

brush border

Question 18

long and branching finger-like projections of the apical epithelial cell surface that contain a core of cross-linked actin but NO AXONEME.

Answer 18

stereocilia

Question 19

Lines lumina of ducts, vessels, and other tubular structures as well as forms walls of alveoli, Bowman’s capsules and inner surfaces of membranous labyrinth and tympanic membrane

Answer 19

simple squamous epithelia

Question 20

In side view, cells may be low or high (approaching almost squamous or almost columnar). May have a brush border (kidney tubules) on apical surface composed
of microvilli. Found on surface of ovary, pigmented epithelium of retina, kidney tubules, glands and ducts, terminal bronchioles, choroid plexus, and anterior capsule of lens of eye.

Answer 20

simple cuboidal epithelium

Question 21

May have a striated border (intestinal cells) on apical surface composed of microvilli. Ciliated version is found in the upper respiratory tract, uterine tubes, uterus, paranasal sinuses, and the central canal of the spinal cord. Non-ciliated version is found in the digestive tract beginning with the cardia of the stomach, the gall bladder, and in parts of the excretory ducts of glands, and is often associated with Goblet Cells.

Answer 21

Simple columnar epithelium

Question 22

Heavily keratinized version is found in the epidermis with connective tissue papillae and in the cornea without connective tissue papillae. Lightly or non- keratinized version is found in the esophagus, vagina, lining of the mouth, tongue, and part of the epiglottis.

Answer 22

stratified squamous epithelium

Question 23

Seldom found, but may occur in small areas of the anal mucosa, large excretory ducts of some glands, and part of the male urethra

Answer 23

Stratified cuboidal epithelium

Question 24

Seldom found; occurs in the ducts of adult sweat glands, fornix of the conjunctiva of the eye, parts of the male reproductive/urinary tract, the pharynx, and the epiglottis

Answer 24

Stratified columnar epithelium

Question 25

ciliated version found in the trachea. Version with stereocilia is found in the epididymis.

Answer 25

pseudostratified epithelium

Question 26

similar to microvilli but are longer and often branched; long, branched, non motile cilia

Answer 26

stereocilia

Question 27

functions primarily in secretion of enzymes and mucous and absorption of nutrients and fluids

Answer 27

simple columnar epithelium

Question 28

indicative of highly keratinized epithelium

Answer 28

absent nuclei in the outermost layer

Question 29

indicative of transitional/urothelium

Answer 29

dome-shaped cells

Question 30

Simple, non ciliated columnar epithelium is most likely to be found associated with what tissue

Answer 30

digestive tract

Question 31

Junctional complexes are associated with which cellular domains?

Answer 31

Basolateral

Question 32

Transitional epithelium is associated with which systems?

Answer 32

Urinary system

Question 33

stratified cuboidal epithelium may be found where

Answer 33

part of male urethra

Question 34

Lightly keratinized stratified squamous epithelium is characteristic of what tissue

Answer 34

vaginal epithelium