integumentary system

Question 1

function of the skin

Answer 1

provides protective barrier against mechanical, thermal, and physical injury under dangerous circumstances

Question 2

5 layers of epidermis
- stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale

Answer 2

sc- outermost layer of epidermis; exists to protect inner layers of skin and is a series of layers of specialized skin cells that are continuously shedding
sl- thin, transparent layer of keratinocytes that are becoming less round and have a flatter shape; serves to protect palsm of hands, side fingers and bottoms of feet
sg- helps form a waterproof barrier that functions to prevent fluid loss from the body; cytoplasmic granules contain keratin and lipid based substances
ss- provides protection against UV light; helps skin become more flexible and strong
sb- innermost layer of epidermis; melanocytes are prsent with sensory recetios called Markel cells (function in light touch and sensory discrimination); single row of actively dividing keratinocytes; home to melanocytes that produce melanin

Question 3

2 layers of epidermis
- papillary and reticular

Answer 3

papillary layer - composed of loose connective tissue; contains fingerlike projections called Dermal Papillae with Tactile Corpuscles detecting fine touch and Capillary loop providing blood supply to the epidermis
reticular layer - with dense irregular collagenous connectve tissue; houses structures like sweat glands, sebaccous glands, blood vessels and lamellated corpuscles with free nerve endings

Question 4

structures found in skin

sebaccous gland

Answer 4

excrine gland secretint sebum

Question 5

sweat glands

Answer 5

exocrine glands secreting sweat through sweat ducts; Ecrine found all over the body; Aprocrine found in axillae and genital region

Question 6

hair

Answer 6

shaft - composed of dead keratinocytes projecting from skins surface

Question 7

root

Answer 7

embedded in dermis

Question 8

hair papilla

Answer 8

projection from dermis indented at the base of the root

hair pailla + hair root = hair bulb

Question 9

hair follicle

Answer 9

sheath where hair is embedded; inner lining cosists of epithelium continous with epidermis

Question 10

arrector pilli muscle

Answer 10

band of smooth muscle attached to hair follicle

Question 11

nails

Answer 11

composed of primarily dead keraitnocytes and nail plate surrounding by nail folds