Integumentary System

Question 1

How much area does the skin cover?

Answer 1

about 2 square meters (22 square feet)

Question 2

How much does the skin weigh?

Answer 2

4.5-5 kg (10-11 lb)

Question 3

What are the 2 layers of skin?

Answer 3

Epidermis and Dermis

Question 4

What is the epidermis derived from?

Answer 4

the embryonic ectoderm

Question 5

What is the dermis derived from?

Answer 5

the embryonic mesoderm

Question 6

What layer is found beneath the dermis?

Answer 6

hypodermis (the subcutaneous tissue)

Question 7

What is the function of the hypodermis?

Answer 7

it anchors the skin loosely to the underlying tissues (muscle)

Question 8

What does the skin do when its hot?

Answer 8

Receptors in the skin send signals to the hypothalamus which will trigger the skin to release water and sodium which will cool the skin via convection

Question 9

What does the skin do when its cold?

Answer 9

Blood vessels constrict to prevent heat loss, there is involuntary muscle contraction (shivering), and the subcutaneous fat preserves heat

Question 10

What is a dermal papilla?

Answer 10

a cone shaped protrusion at the base of the follicle which feeds blood and therefore nutrients to the hair bulb

Question 11

What is a sebaceous (oil) gland?

Answer 11

a gland that lubricates and keeps the hair healthy and shiny

Question 12

What is an arrector pili?

Answer 12

a tiny muscle anchored to the follicle that contracts and make the hair stand up straight

Question 13

What 2 types of stimuli do arrector pili respond to?

Answer 13

scary and cold stimuli

Question 14

What type fiber types are found in the dermis?

Answer 14

collagen and elastin

Question 15

What is the function of the dermis?

Answer 15

It provides skin tone and accounts for the strength and toughness of the skin

Question 16

What structures are found in the dermis?

Answer 16

Vascular tissue
Afferent nerve endings
Hair

Question 17

What is the hypodermis composed of?

Answer 17

mainly adipose tissue plus some areolar tissue

Question 18

What are the 3 types of burns from least sever to most?

Answer 18

1) 1st degree (superficial)
2) 2nd degree (partial thickness)
3) 3rd degree (full thickness)

Question 19

What layers of the skin are damaged in a 1st degree burn?

Answer 19

just the epidermis (sunburn)

Question 20

What layers of the skin are damaged in a 2nd degree burn?

Answer 20

the epidermis and into the superficial part of the dermis

Question 21

What is characteristic of a 2nd degree burn?

Answer 21

blisters

Question 22

What layers of the skin are damaged in a 3rd degree burn?

Answer 22

The entire epidermis and dermis are destroyed, and part of the hypodermis is damaged

Question 23

What is characteristic of a 3rd degree burn?

Answer 23

loss of bloodplasma by exudation and often times blackened skin

Question 24

What is required in order for a 3rd degree burn to heal?

Answer 24

a skin autograph

Question 25

What is cyanosis?

Answer 25

It is a blue discoloration of the skin caused by an excess of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule

Question 26

If a person suffers a burn on the forearm that destroys the epidermis and a portion of the dermis would you expect to find hair growing in the area of the injury after it heals?

Answer 26

Yes, because it does not damage the subcutaneous layer where the hair receives it’s blood supply and nutrients