Histology

Question 1

What are the three regions of the epithelium?

Answer 1

Basal- the bottom
Apical- the side that will face the outside/lumen
Lateral- the sides that communicate with each other

Question 2

What are microvilli?

Answer 2

Cytoplasmic projections that have an actin core. They are generally used in absorption and seen in the gastrointestinal system

Question 3

What is stereocilia?

Answer 3

They are microvilli that are longer in length. Appear to be hair like projections with an actin core. They are generally restricted to the epididymis and the inner ear

Question 4

What are cilia?

Answer 4

There are longer hair like projections that have a microtubule core. They have three main functions- motility(movement) primary(chemoreception) and nodal(axis for embryo)

Question 5

What are flagella?

Answer 5

They are modified motile cilia used mostly in sperm cells

Question 6

What is an occluding junction?

Answer 6

It is a cellular junction that decreases the permeability of the cell layer. They are generally lateral but more towards the apical surface and use occluding/claudins as molecules.

Question 7

What is an anchoring junction?

Answer 7

They are lateral adhesions that link into the cytoskeleton of the adjacent cell- Two types zonula and macula

Question 8

what is the difference between the zonula and macula anchoring junctions?

Answer 8

The zonula work with the actin filaments while the macula(also known as desmosome) will be intermediate filament, more specifically the Catherine’s

Question 9

What is a Gap junction?

Answer 9

They allow communication between cells by providing a fluid filled channel that use connexin aggregates

Question 10

What are focal adhesions?

Answer 10

Uses actin filaments using integrins to attach cells to the basement membrane

Question 11

What are hemidesmosomes?

Answer 11

Anchor intermediate filaments using integrins to the basement membrane

Question 12

What is a simple squamous epithelial layer?

Answer 12

A cell type that lines blood vessels, serous membranes and avola- they function in fluid exchange of material, act as a barrier and lubrication

Question 13

What is simple cuboidal epithelial tissue?

Answer 13

Located in the kidney tubules, glands/ducts, covering ovary- they function in absorption, barrier and secretion

Question 14

What is simple columnar epithelial tissue?

Answer 14

They are located in the auditory tubes, uterus, oviducts, stomach and gall bladder- they function in absorption and secretion

Question 15

What is pseudostratified columnar ciliated epithelial tissue?

Answer 15

Line the nasal cavity, pharynx, trachea and bronchi- they have cilia projections on the top- function in absorption/secretion and will help clear debris/particulate movement

Question 16

What is urothelium epithelial tissue?

Answer 16

These cells are domed located in the urinary bladder, uterus and uretha- they function in barrier and have distensible properties

Question 17

What are non keratinized stratified squamous cells?

Answer 17

Located in the oral cavity, esophagus, anus and vagina they function as a barrier or protection from the outside. The most apical cells have a nucleus

Question 18

What are keratinized stratified squamous cells?

Answer 18

They are located in the epidermis of the skin and function as a barrier- these most apical cells do not have a nucleus and they are covered by a layer of keratin

Question 19

What is stratified cuboidal cells?

Answer 19

They are located in the sweat glands, ovarian follicles and function as a passage way or barrier

Question 20

What is a mucous membrane?

Answer 20

A specialized epithelial tissue that secretes mucous in places like the respiratory tract and body cavities

Question 21

What is a serous membrane?

Answer 21

A specialized membrane that secretes fluid to allow tissues to slide against eachother- found in places like the heart

Question 22

What is a merocine gland?

Answer 22

The secretion is delivered to the apical surface by a vesicle then undergoes exocytosis

Question 23

What is a holocrine gland?

Answer 23

These cells will accumulate product in cell then undergo apoptosis, releasing the product as it degrades

Question 24

What is an apocrine gland?

Answer 24

The product, typically lipid based, is budded off into a membrane at the apical surface of the cell then leaves duct

Question 25

What are the two sections of multicellular glands?

Answer 25

The ancinus and duct portions- the ancinus is the part that will secrete mucous or serous fluids

Question 26

How can you differentiate serous ancini from mucous ancini?

Answer 26

Serous ancini will generally pick up stain very well while the mucous does not