epithelia III A

Question 1

Glands of the body are derived from _____.

Answer 1

epithelial tissue

Question 2

Glands are found _______.

Answer 2

in many sites of the body, often associated with the epithelia of body surfaces and cavities, and as components of specific organs.

Question 3

The primary function of glands is ______

Answer 3

secretion of either specific bioactive molecules (e.g. hormones), complex fluids (e.g. mucous, sweat), or both.

Question 4

There are two major types of epithelial glands:

Answer 4

1. Exocrine glands that secrete materials onto epithelia-lined surfaces or the outside world.
2. Endocrine glands that secrete substances into the blood stream

Question 5

Glands secrete their substances in one of two general ways.

Answer 5

(1) Exocytosis

(2) holocrine glands

Question 6

Exocytosis:

Answer 6

most common mechanism

also called merocrine or apocrine glands.

Question 7

holocrine glands

Answer 7

Total cell disintegration, which leads to the entire cellular contents becoming part of the secretion;
–less common

Question 8

holocrine glands examples:

Answer 8

the secretion of oily sebum onto hair and skin

Question 9

Exocrine glands secrete materials onto the _____.

Answer 9

apical side of epithelial surfaces

Question 10

exocrin are generally:

Answer 10

multicellular

Question 11

Some epithelial cells in the lining of internal passageways function as ____

Answer 11

unicellular glands secreting materials directly onto those surfaces (e.g. goblet cells).

Question 12

All multicellular exocrine glands have two main components:

Answer 12

1. secretory units

2. ducts

Question 13

The Secretory units are:

Answer 13

clumps of secretory epithelial cells, which produce and secrete the bulk of the secretion.

Question 14

Secretory units can be organized into:

Answer 14

bowl or flask-shaped lobules called alveoli or acini, and are called alveolar or acinar glands, or they may be organized into tubes, and are called tubular glands.

Question 15

Some glands have both tubular and alveolar character and are called ______.

Answer 15

tubuloalveolar

Question 16

Some glands can have:

Answer 16

a single secretory unit or they may have multiple branched units

Question 17

Ducts are:

Answer 17

tubular structures that emanate from the secretory units.

Question 18

Ducts function as:

Answer 18

passageways to conduct secretions to their destinations, although their epithelia can also modify the secretion content by secretory and ion transport properties of duct cells.

Question 19

Glands that possess a single duct are classified as _______.

Answer 19

simple glands, whereas those with multiple branched ducts are called compound glands.

Further subclassifications exist reflecting whether the glands is coiled, and whether the secretory units are multilobed (branched) or not.

Question 20

exocrine glands of the body “tubes” (alimentary canal, respiratory, and urogenital systems) are of three general types:

Answer 20

1. mucous
2. serous
3. mixed

Question 21

mucous:

Answer 21

from which a viscous glycoprotein-rich fluid is produced

Question 22

serous:

Answer 22

from which a watery fluid, containing salts and some specific proteins, is produced

Question 23

mixed:

Answer 23

from which both kinds of secretions are produced.

Question 24

secretory epithelial cells of these glands secrete materials _____

Answer 24

unidirectionally from their apical surface (with the exception of holocrine secretion)

Question 25

Endocrine glands have _____

Answer 25

no ducts and secrete substances to the blood stream.

Question 26

Endocrine glands produce

Answer 26

mostly specific hormones that act over relatively long distances to control tissue function.

Question 27

Endocrine glands are generally organized as

Answer 27

clumps or chords of cells that are embedded with and surrounded by connective tissue containing extensive capillary networks.

Question 28

Blood capillaries are imbedded in

Answer 28

connective tissue on the other side of the epithelial basal lamina.

Question 29

hormone molecules must cross the _______ to reach the blood stream.

Answer 29

basal surface and basal lamina of the epithelium (and finally the basal lamina and endothelial layer of the capillary)

Question 30

each endocrine clump is surrounded by

Answer 30

a basal lamina.

Question 31

most endocrine cells secrete hormone molecules from the _____ membrane

Answer 31

basolateral