Chapter 5 - Integumentary System

Front 1

Integumentary System - What is it composed of?

Back 1

1) Skin
2) Hair.
3) Nails.
4) Sebaceous glands.
5) Sweat Glands.

Front 2

Skin - 4 main functions?

Back 2

1) Protection.
2) Regulation.
3) Sensation.
4) Secretion.

Front 3

Skin Protects - 6.

Back 3

1) Protective membrane against invasion by bacteria & other harmful agents.
2) Mechanical injury of delicate cells underneath epidermis/outer covering.
3) Inhibits excessive loss of water and electrolytes.
4) Reservoir for storing food and water.
5) Guards body against excessive exposure to ultraviolet rays - produces a protective pigmentation.
6) Helps produce body's supply of Vitamin D.

Front 4

Skin Regulates:

Back 4

Body temperature.
1) Cool body/lose heat:
a) Blood vessels dilate- bring more blood to surface for radiation cooling.
b) Sweat glands secrete more sweat for evaporation cooling.
2) Heat body/conserve heat:
a) Nervous system constricts skin's blood vessels so allowing more heat-carrying blood to circulate to muscles and vital organs.

Front 5

Sensation

Back 5

Millions of microscopic nerve endings that act as sensory receptors for pain, temperature & pressure.
Stimulation - nerve impulses sent to cerebral cortex to trigger necessary response.

Front 6

Secretion.

Back 6

Sweat glands - secrete perspiration/sweat - water with small amount of salt & other chemical compounds. When left to accumulate, secretion causes body odor, especially when trapped by hairs in the axillary region.
Sebaceous glands - secrete oil/sebum for lubrication - acts to protect body from dehydration and possible absorption of harmful substances.

Front 7

Skin - Two Layers.

Back 7

Epidermis - 4 sub strata.
Dermis/true skin/corium.

Front 8

Epidermis - 4 stratum.

Back 8

Corneum - outermost, horny layer of dead cells filled with protein substance KERATIN. Formms protective covering for body and thickness varies with body use.

Lucidum - Translucent layer lying directly beneath CORNEUM. Frequently absent and not seen in thinnner skin. Cells in Lucidum also dead/dying.

Granulosum - Several layers of LIVING cells that are becoming part of the previous layer. Cells active in KERATINIZATION process, during which they lose their nuclei and become hard/horny.

Germinativum/mucosum/malpighii - several layers of LIVING cells capable of MITOSIS/cell division - responsible for regeneration of epidermis. Damage to Germinativum necessitates use of skin grafts. Melanin formed in this layer.

Front 9

Dermis/Corium/True Skin.

Back 9

Composed of connective tissue that contains:
lymphatics,
nerves and nerve endings,
blood vessels,
sebaceous and sweat glands
elastic fibers
hair follicles.

Front 10

Dermis has two layers:

Back 10

1) Upper/papillary layer.
2) Lower/reticular
Dermis attached to underlying structures by SUBCUTANEOUS TISSUE that supports, nourishes, insulates and cushions skin.