chapter 5 integumentary system

stratum basale

deepest layer; one layer thick; mytosis occurs here;

UV light, bacterial invasion and dehydration

What are some examples of how the integumentary system protects the body?

nerve endings and receptors that detect temperature, touch, pressure and pain

What are some examples of how the integumentary system helps us to feel or sense things?

protection, body temprature regulation, sensation, excretion, blood reservoir and metabolic function

What are the six functions of the integumentary system?

sweating

What is an example of how the integumentary system regulates body temperature?

stores large amount of blood in the skin so that it can be shunted elsewhere as needed

What is the role of the integumentary system as a blood reservoir?

synthesizes vitamin d with help of uv light

What is the role of the integumentary systems in metabolic function?

removal of wastes through sweat (i.e. uric acid)

What role does the integumentary system have in excretion?

thick skin

five layers; located on palms of hands, fingertips and soles of the feet

thin skin

four layers; located everywhere on the body except on palms of hands, fingertips and soles of the feet.

hypodermis

located just below the dermis where fat is; superficial fascia;

stratum corneum

on top of statum ludicium; outside layer; 20 to 30 cells thick; provides protection from external environment, dead cells ready to be shed; thicker in thin skin (more layers found in these areas);

stratum spinosum

on top of stratum basale; several layers thick; has a lot of anchoring junctions; spiky and spiny in appearance;

stratum lucidium

on top of stratum granulosum; clear layer; found only in thick skin;

stratum granulosum

on top of stratum spinosum; 3 to 5 cell layers thick; contains keratohyaline granules (aggregations of keratin); gives epidermis its protective properties; contains lamellated granules, which are cells that interconnected in sheets like shingles on roof; provides waterproofing;

melanin

protects the nucleus of cells from uv radiation found in sunlight;

epidermis

stratified squamous keratinized epithelium

the skin

what is the protective barrier in the integumentary system

keratinocytes

these are the majority of skin cells; they produce keratin (hardening agent)

thick and thin skin

two types of skin in the epidermis are?

melanocytes

we have a few of these type of cells; Found only in the stratum basale; all other areas contain keratinocytes; they produce melanin which is a pigment used to protect us from UV radiation;

7%

what % of body weight is made up of skin?

keratinocytes, melanocytes and dermis

what are the cells of the epidermis

epidermis and dermis

what are the two regions of the skin?