Integumentary System

Front 1

1. layers of system (epidermis)

Back 1

Mostly stratified squamous epithelium
1. basale - cells that divide
2. spinosum
3. granulosum - keratohyaline granules
4. lucidum - not present in thin skin
5. corneum - no nuclei or organelles, dead cells with lots of keratin

Front 2

2. layers of system (dermis) - connective tissue

Back 2

1. papillary layer (pg. 64)
2. reticular layer - tough, leathery. 3d arrangement of collagen fibers

Front 3

3. hypodermis / subcutaneous tissue

Back 3

1. loose CT under fat and dermis (separated by basement membrane)

Front 4

Functions

Back 4

1. protection: wide range of protection. enchanced by gland secretion, increased pigment, or hypertrophy
2. prevent dehydration
3. perception of sensation
4. synthesis of vitamin D
5. temperature regulation (via sweat and vasodilation)

Front 5

Functions cont

Back 5

6. waste excretion
7. absorbs lipid soluble agents
8. barrier between outside and internal agents
9. stores glycogen and functions in glucose metabolism
10. functions in fluid electrolyte balance

Front 6

Skin types

Back 6

1. thick - palms of hands, soles of feet. thick epidermis. no hair 100 cells thick
2. thin skin - anyplace else. hairy 15-25 cells thick

Front 7

Accessory Organs

Back 7

1. Hairs
2. Sebaceous glands
3. Sweat glands
4. Nails

Front 8

Hair

Back 8

keratinized filament developed via invagination of epidermis. Has pili muscle which contracts when cold to reduce surface area of skin

Front 9

Hair structure

Back 9

1. external root sheath - outermost portion
2. bulb - deep part created by invagination of CT
3. internal root sheath
(slides 20 and 21 of pgs 70 and 71)

Front 10

sebaceous glands

Back 10

secrete oily sebum. ducts open into hair follicle. hair and skin soft and waterproof. prevents excessive evaporation.

Front 11

Sweat glands

Back 11

carries heat from body. Numerous in palms and soles. mammary glands are modified sweat glands.
Two types apocrine and eccrine

Front 12

Apocrine

Back 12

active during stress read 25

Front 13

eccrine

Back 13

more numerous than apocrine. secrete in response to increased body temperature

Front 14

Nails

Back 14

modified epidermis with a protective function.

Front 15

Nail components

Back 15

eponychium - dead skin along proximal border of margin of nail fold
hyponychium - located beneath
lunule - partially keratinized, white distal to nail fold
nail plate on nail bed