Integumentary System

Question 1

What does the integumentary system consist of?

What is the % of total body mass?

Answer 1

Skin, hair, nails, sebaceous glands and sweat glands

15-20% of total body mass

Question 2

Functions of integumentary system

Answer 2

• synthesis of vitamin D
• protection from dehydration and infection
• temp regulation
• excretion of water, salts, urea
• respond to temp, pressure and pain
• first immune response

Question 3

Give functions for each layer

Answer 3

Epidermis- protects, keeps body hydrated, contains melanin, produces skin cells

Dermis- fiborous structure, contains nerve endings, hair follicles and glands. Protects and assists with thermoregulation, aids with sensation

Hypodermis- stores energy, connects dermis to muscle and bones, insulates body

Question 4

Homeostatsis model for thermoregulation
- increase in body temp

Answer 4

Stimulus -Increase in core temp

Receptor- thermoreceptor (free nerve endings in skin) detect rise in temp

Control centre- Hypothalamus

Effector- sweat glands produce sweat- evaporates cooling the skin
Arteries dilate to release heat
Muslce relaxes- hair lies flat

Effect- normal temp restored

Question 5

Homeostasis model for thermoregulation

Answer 5

Stimulus- drop in core temp

Receptor- thermoreceptors (free nerve endings in skin) detect change

Control centre- Hypothalamus

Effector- blood vessels contrict- reduces blood flow to skin to prevent heat loss
Sweating inhibted
Shivering - muscle contractions to generate heat
Arrector pilli muscles contract to make hair stand to trap air for insulation

Effect- body temp increases/regulates

Question 6

What are the stages of wound healings and outline what happens in each

Answer 6

1. Hemostatasis - blood clotting, first response to seal wound

2.Inflammation- redness, pain and swelling- blood vessels dilate and leucycytes enter

3.Proliferation- formation of granlation tissue- new connective tissue and blood vessels replace damaged tissue- collagen and fibroblast activty

4.Remodelling/Maturation- final stage- collagen production, scar formation is less elastic and weaker then pre-injured skin

Question 7

Five cardinal signs of acute inflammation

Answer 7

Calor/ Heat
- vasodilation occurs to increase temp to extremities

Dolor/Pain
- the release of chemical mediators and swelling stimuates pain receptors/nerve endings

Rubor/Redness
- increased blood flow/hyperaemia pools rbc in capillaries

Tumor/Swelling
- increased permability of blood vessels allowing fluid and white blood cells to move into interstitial tissue

Funtio laesa/Loss of function
- pain and swelling limit movement

Question 8

Mole considerations for concerning presentation

Answer 8

A- Asymmetry
B- Border
C- Colour
D- Diameter
E- Evolving- changes in size, shape or begins to bleed or scab

Question 9

What are the teo types of aging processes?

Answer 9

Intrinsic - affects skin of entire body
Extrinsic- induced by chronic UV radiation, smoking, and pollutants