Chapter 2- Tissue types (3)

Question 1

Where do all epithelial sheets rest?

Answer 1

On a basement membrane that helps it resist stretching and tearing.

Question 2

What is the basal surface?

Answer 2

The side of the epithelium that rests on the basement membrane

Question 3

What is the apical surface?

Answer 3

The other free side of the epithelium

Question 4

Most apical surfaces are covered with what?

Answer 4

Microvilli or cilla- hairs that are important for movement and sensation, e.g, hearing

Question 5

How is covering epithelia classified?

Answer 5

1- Based on the shape of the cells

2- The number of layers

Question 6

What are the three primary types of shape for covering epithelia?

Answer 6

1- Squamous
2- Cuboidal
3- Columnar

Question 7

What are the two types of layers for covering epithelia?

Answer 7

1- Simple layer- one layer

2- Stratified layer- multiple layers

Question 8

What is simple epithelia useful for?

Answer 8

When an exchange of substances is required

Question 9

What is stratified epithelia useful for?

Answer 9

Protection

Always found in areas subject to abrasion, e.g, skin, cornea

Question 10

Stratified epithelia are usually what in humans?

Answer 10

Squamous

Question 11

Altogether, there are 8 types of epithelia. Give some examples

Answer 11

Simple squamous, Simple cuboidal, simple columnar, etc.

Question 12

The other two types of epithelia are what?

Answer 12

1- Pseudo stratified- simple columnar epithelia that look stratified

2- Transitional- cells that are round in shape when the organ is relaxed, but flatten when there is pressure e.g, the bladder

Question 13

What forms the various glands of the body?

Answer 13

Glandular epithelial cells

Question 14

What is a gland?

Answer 14

A group of cells that make and secrete a particular product

Question 15

What is the gland involved in?

Answer 15

The production and release of many different secretory products, such as sweat, saliva, and hormones.

Question 16

What are the types of glandular secretion?

Answer 16

1- Serous- a watery substance often containing proteins, e.g, saliva

2- Mucous- a thick, sticky substance

3- Sebaceous- an oily substance, e.g, in the armpit

Question 17

Glands are classified as either…

Answer 17

1- Exocrine glands- secrete their products onto the epithelial surface

2- Endocrine glands- secrete hormones into the interstitial fluid, where they go on to enter the blood.

Question 18

Give an overview of endocrine glands

Answer 18

Structurally diverse and most are multicellular.

Generally ductless

Their secretions are varied

Question 19

In multicellular exocrine glands, where do secretions travel?

Answer 19

Up to the surface via a series of connecting cells that form a duct.

Question 20

What is a unicellular exocrine gland?

Answer 20

When a single cell produces and secretes

Question 21

What is the most common example of a unicellular exocrine gland?

Answer 21

Mucus secreting goblet cell.

Question 22

Where are goblet cells found?

Answer 22

In the epithelium of the trachea and digestive tube (to protect/ lubricate)

Question 23

What is a multicellular exocrine gland?

Answer 23

Consists of groups of secretory cells connected to a free surface by ducts.

Question 24

If there is only a single duct in a multicellular exocrine gland, what is it called?

Answer 24

Simple

Question 25

If there are multiple ducts in a multicellular exocrine gland, it is called?

Answer 25

Compound

Question 26

Multicellular exocrine glands can be classified based on:

Answer 26

1- Shape of their secretory units
2- Mode of secretion

Question 27

What are the different shapes of secretory units?

Answer 27

1- Tubular- if secretory units form tubes.
2- Alveolar- if secretory units form small hollow cavities.
3- Can also be a bit of both- tubuloalveolar

Question 28

What are the different modes of secretion for multicellular exocrine glands?

Answer 28

1- Merocrine- if the product is released via exocytosis

2- Holocrine- if whole cell ruptures to release product.

3- Apocrine- tip of cell is shed and cell repairs the damage.