integument structure

Question 1

what are the layers of the skin (3)

Answer 1

1. epidermis
2. dermis
3. hypodermis

Question 2

what is the process of keratinization?

Answer 2

• cells pushed up from the basal layer to the epidermis layer
• produce tough keratin, the tough, fibrous, waterproof protein that gives skin it’s resiliency and strength

Question 3

what is the process of pigmentation?

Answer 3

caused by the presence of, or lack of, melanin granules

Question 4

what are the features of the paw pads

Answer 4

• paw pads are the thick layers and connective tissue and exocrine sweat glands
• the outer surface is the toughest skin on the body
• has all five epidermal layers

Question 5

what are the features of the planum nasale

Answer 5

“nose”
- top of the nose in cats, pigs, and dogs
- has three epidermal layers

Question 6

what are the parts of the hair follicle?

Answer 6

1. hair shaft - visible above the skin
2. hair root - buried within the skin
3. hair follicle - anchors the hair

Question 7

what is the hair growth cycle?

Answer 7

1. Anagen phase: cells are added at the base of the root, hair lengthens
2. Catagen phase: period of transition between anagen and telogen phases
3. Telogen phase: maximum length of hair is achieved, hair stops growing, follicle shortens, & hair is held in resting place

Question 8

what are the three types of hair

Answer 8

1. primary or guard hair
2. secondary or wool-type hair
3. tactile (or “sinus”) hairs

Question 9

Primary “guard” hair functions

Answer 9

straight or arched; thicker and longer than secondary hairs

Question 10

Secondary “wool-type” hairs

Answer 10

“puppy coat”
softer and shorter than primary hairs; wavy or bristled in the dog

Question 11

Tactile “sinus” hair

Answer 11

contain numerous sensory ending, commonly known as whiskers (can also be intermixed throughout coat)

Question 12

List the three sebaceous glands

Answer 12

1. sweat glands
2. tail glands
3. anal sacs

Question 13

function of sweat glands

Answer 13

helps cool the body through evaporation

Question 14

function of tail glands

Answer 14

communication, territory marking, helps identify one another with scent

Question 15

function of anal sacs

Answer 15

line with sebaceous and apocrine glands, when defecation occurs some to all contents are expressed