Ch 4, 2 epithelial tissues

Question 1

covering and lining epithelia

Answer 1

on external and internal surfaces, eg skin, serous membranes

Question 2

glandular epithelia definition

Answer 2

secretory tissue in glands, eg. goblet cells, gastric glands

Question 3

five common characteristics of epithelium

Answer 3

1. cells have polarity-apical and basal
2. composed of closely packed cells
   3.supported by a connective tissue reticular lamina (under the basal lamina)
   basal membrane=basal lamina/reticular lamina
3. Avascular but innervated
4. high rate of regeneration

Question 4

classification on epithelia

Answer 4

1. number of layer
a, simple
b. stratified
2. shape of the cells
a. squamous
b. cuboidal
c. columnar

Question 5

gland

Answer 5

one or more cells that make and secrete a product

Question 6

endocrine glands

Answer 6

ductless glands that secrete hormones by exocytosis
directly into the blood or lymph
travel to target organ which has appropriate membrane receptor or enter cells

Question 7

exocrine glands

Answer 7

more numerous that endocrine
secrete products into ducts onto body surfaces
release secretions onto body surfaces or into body cavities
ex, mucous, sweat, oil and salivary glands

Question 8

types of exocrine glands

Answer 8

classified by number of cells, structure and mode of secretion

1. unicellular glands-goblet cells
2. multicellular glands- composed of duct and secretory unit

Question 9

types of multicellular exocrine glands

Answer 9

duct type= simple or compound

secretory units=tubular, alveolar(sac), tubuloalveolar

Question 10

merocrine

Answer 10

products are secreted by exocytosis
cells are long lived because they are not damaged during product release
–pancreas, sweat and salivary glands

Question 11

holorine

Answer 11

product accumulates in apical cells and are released by rupture of cells
replaced by mitosis of basal cells
–sebaceous glands (oil)