Integumentary

Question 1

in an average adult, the skin covers about how many meters?

Answer 1

2 square meters

Question 2

how much does the skin weigh on the average adult?

Answer 2

10-11 lbs

Question 3

how many layers does the skin consist of?

Answer 3

2

Question 4

what are the two layers of skin? what do they consist of?

Answer 4

epidermis: derived from the embryonic ectoderm dermis: which develops from the mesoderm.
The appendages of the skin such as hair, nails, sebaceous glands and sweat glands develop from the embryonic epidermis.

Question 5

what layer is beneath the dermis?

Answer 5

hypodermis: (=subcutaneous tissue = superficial fascia) which anchors the skin loosely to underlying tissues (mainly muscles). The hypodermis is NOT part of the skin

Question 6

what are the functions of the skin and its appendages (hair, nails, sebaceous, and sweat glands)

Answer 6

1. Protection: barrier against the outside
2. Body Temperature Regulation
3. Cutaneous Sensation
4. Synthesis of Vitamin D: Bones do not ossify properly
5. Excretion

Question 7

what are some examples of heat transfer?

Answer 7

conduction, convection, radiation

Hot: 1.Receptors in your skin send signal to the hypothalamus
2. Sweat releases water and Na (Convection) Skin cools

Question 8

list the mechanisms involved in the cold stimulus

Answer 8

1. Constrict blood vessels. Prevent heat loss to keep the core temp intact. 2. Decrease the production of sweat 3. Increase shivering (involuntary muscle contraction) 4. Subcutaneous fat preserves heat

Question 9

dermal papilla

Answer 9

(a cone shaped protrustion at the base of the follicle which feeds blood - and therefore nutrients - to the hair bulb).

Question 10

sebaceous gland

Answer 10

(or oil gland) which lubricates and keeps the hair healthy and shiny.

Question 11

Arrector pili

Answer 11

a tiny muscle anchored to the follicle. The arrector pili respond to stimulus (fear or cold) causing them to contract and make the hair stand up straight.

Question 12

what tupes of fibers does the dermis consist of?

Answer 12

a dense layer of collagen and elastic fibers.
These fibers provide skin tone and account for the strength
and toughness.

Question 13

what types of nerve endings does the dermis have?

Answer 13

afferent nerve endings

Question 14

is the dermis highly vascular or minimally vascular?

Answer 14

highly vascular

Question 15

hypodermis

Answer 15

(= subcutaneous tissue = superficial fascia) is NOT part of the skin. It consists mainly of adipose tissue plus some areolar tissue. “Beer belly” in man and thick thighs and buttocks in female are due to too much fat stored in the hypodermis of these regions of the body.

Question 16

first degree burn

Answer 16

(superficial) the damage is limited to the superficial part of the epidermis.

Question 17

what are burns?

Answer 17

Burns are injuries caused by thermal, electrical, radioactive, or chemical agents

Question 18

second degree burn

Answer 18

(partial thickness): the damage extends through the epidermis into the superficial part of the dermis.

Question 19

third degree burn

Answer 19

(full thickness): the entire epidermis and dermis are destroyed. Loss of blood plasma by exudation from the burn site occurs. Skin autograph is required for skin healing.

Question 20

what layer(s) does a first degree burn effect?

Answer 20

epidermis, only redness

Question 21

what layer(s) does a second degree burn effect?

Answer 21

epidermis and dermis, with blistering

Question 22

what layer(s) does a third degree burn effect?

Answer 22

full thickness, destroying epidermis, dermis, often part of hypodermis

Question 23

what effects does aging have on the integumentary system?

Answer 23

More prone to injury: epidermis thins decreased germination
Sensitivity of skin decreases
Vitamin D production declines
Galndular activity declines. Skin becomes dry
Blood supply to the skin decreases: High internal temp
Dermis becomes thin.
Leads of skin infection.

Question 24

what causes cyanosis (blue discoloration) of the skin?

Answer 24

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