Skin

Question 1

A bit about skin…?

Answer 1

aka integument
outer barrier & interface to environment
important protective barrier - decrease water loss; invasion of microbes; traumatic abrasions; major site for stimulation of immune sys.
largest organ of body!!!

Question 2

Functions of skin…?

Answer 2

• protect body against mechanical, chemical, physical & bio. factors within environment
• receptors for perception of pressure, pain, temp. (heat & cold)
• storage & excretion of water, electrolytes, & fat
• synthesis of vit. D3
• thermoreg.
• immunological defence
• communication

Question 3

3 layers of skin…?

Answer 3

epidermis
dermis
hypodermis

Question 4

A bit about the epidermis…?

Answer 4

outer layer of skin - continuous with mucous membranes
avascular stratified squamous epithelium nearly free of nerve endings
contains: keratinocytes, melanocytes, & Langerhans cells (drying of these superficial cells -> keratinisation & cornification -> tough skin & resistant to drying)
relies of diffusion of nutrients
callus: local increase in thickness in response to continuous trauma

Question 5

What are the 5 layers in the epidermis…? deepest -> superficial

Answer 5

1. stratum basale (germinativum)
2. stratum spinosum
3. stratum granulosum
4. stratum lucidum
5. stratum corneum