2.1

Question 1

• These are specialized layers that line the internal and cover the external surfaces of the body.
• They consists of a sheets of cells lying close together with little intercellular space.
• These cells have distinct biochemical, functional, and structural domains that confer polarity, or sidedness

Answer 1

Epithelia

Question 2

This _____ separates the epithelium from underlying connective tissue and blood vessels.

Answer 2

Basement membrane

Question 3

Epithelia are __________ and receive nourishment by diffusion of molecules through the _______________

Answer 3

Avascular; Basal lamina

Question 4

Epithelia are classified into various types on the basis of the _______ of cell layers (one cell layer is simple; more than one is stratified) and the _____ of the superficial cells

Answer 4

Number; shape

Question 5

______________ epithelia appear to have multiple cell layers, but all cells are in contact with the basal lamina.

Answer 5

Pseudostratified

Question 6

Transcellular transport of molecules from one epithelial surface to another occurs by various processes, including the following:

Answer 6

Diffusion, Carrier protein-mediated transport, Vesicle-mediated

Question 7

____________________ of molecules from one epithelial surface to another occurs by various processes, including the following:
- Diffusion
- Carrier protein mediated transport
- Vesicle-mediated transport

Answer 7

Transcellular transport

Question 8

____________ of oxygen and carbon dioxide across the epithelial cells of lung alveoli and capillaries

Answer 8

Diffusion

Question 9

____________________ transport of amino acids and glucose across intestinal epithelia

Answer 9

Carrier protein–mediated

Question 10

______________ transport of immunoglobulin A (IgA) and other molecules

Answer 10

Vesicle-mediated

Question 11

_____________ occurs via endocytosis or pinocytosis in various organs (e.g., the proximal convoluted tubule of the kidney).

Answer 11

Absorption

Question 12

Absorption occurs via __________ or __________ in various organs (e.g., the proximal convoluted tubule of the kidney).

Answer 12

Endocytosis or Pinocytosis

Question 13

_________ of various molecules (e.g., hormones, mucus, proteins) occurs by exocytosis.

Answer 13

Secretion

Question 14

Secretion of various molecules (e.g., hormones, mucus, proteins) occurs by ____________.

Answer 14

Exocytosis

Question 15

_______________ results from the presence of tight junctions between epithelial cells and permits fluids with different compositions and concentrations to exist on separate sides of an epithelial layer (e.g., intestinal epithelium).

Answer 15

Selective permeability

Question 16

Selective permeability results from the presence of ___________ between epithelial cells and permits fluids with different compositions and concentrations to exist on separate sides of an epithelial layer (e.g., intestinal epithelium).

Answer 16

Tight junctions

Question 17

Protection from abrasion and injury is provided by the _________, the epithelial layer of the skin.

Answer 17

Epidermis