Transcript Integumentary System - Fulton County Schools

The Integumentary System
The skin is the body’s
largest organ
Each square inch
of human skin
consists of
twenty feet of
blood vessels.
The Integumentary System
It’s the Skin We’re In!
The epidermis is the topmost layer. It helps to prevent
evaporation of water from the body and to protect the
internal layers from harm.
The dermis is the middle layer. It contains the blood
vessels, nerves, hair roots, and sweat glands.
The subcutaneous tissue is the deepest layer. It contains
fats and connective tissue along with large blood
vessels and nerves.
Why do fingers and toes
wrinkle in the bathtub?
The Integumentary System
It’s a Hairy Situation!
Hair color is determined by the amount and type of
melanin present.
Melanocytes become less active with age. Gray hair is a
mixture of pigmented and non-pigmented hairs.
Red hair results from a modified type of melanin that
contains iron.
The shape of the hair shaft determines texture.
Round shaft – straight hair
Oval shaft – wavy hair
Flat shafts – curly or kinky hair
Alopecia is the term for hair loss.
Why do men have to
shave everyday?
Why do we get
goose bumps when it is cold?
The Integumentary System
Don’t sweat it!
Sebaceous glands or oil glands secrete the sebum an oily
product. Sebum is usually secreted into a hair follicle.
Sebum is a natural skin cream: it helps hair from
becoming brittle, prevents excessive evaporation of water
from the skin, keeps the skin soft and contains a
bactericidal agent that inhibits the growth of certain
bacteria.
Eccrine glands are the most common sweat gland . They
produce sweat, a watery mixture of salts, antibodies and
metabolic wastes. Sweat prevents overheating of the body
and thus helps regulate body temperature.
How much do we sweat
in a day?
The Integumentary System
Red, Yellow, Black or White
The red and yellow hues of the skin are due to
hemoglobin in the red blood cells, which pass through the
capillaries beneath the epidermis, and carotene (yellowish
pigment), which accumulates in fat cells found in
the dermis and hypodermis
The brown in skin color is due to melanin, which is
produced in the skin itself in cells called melanocytes.
These cells are located in the epidermis. Melanin
protects the chromosomes of mitotically active basal
cells against light-induced damage
Malfunctioning Melanocytes
Albinism – melanocytes completely fail to secret
melanin. Hair, skin, and iris are white.
Vitiligo – loss of pigment in certain areas of the skin
producing white patches.
Freckles and moles are formed when melanin becomes
concentrated in local areas.
Malignant melanoma – a cancerous change in a mole
that may metastasize (spread) rapidly and is most
difficult to treat. Exposure to sunlight increases risk.
What can cause a
baby to turn orange?
The Integumentary System
Guiness Book of Records
Functions of the Skin
Protection
Barrier Function
Resistance to wear and tear
Vitamin D Production
Protection from UV light
Sensations
Temperature regulation
Red with embarrassment!
White from fright!
You have approximately 19,000,000 skin cells on every square
inch of your body.
Humans shed about 600,000 particles of skin every hour –
about 1.5 pounds a year.
House dust is mainly skin flakes!
Skin weighs about 2.5 kilograms - the largest organ in the
body.
What hurts if you pull it, but doesn't hurt if you cut it? Your
hair, of course!
Skin is elastic - it springs back into shape when stretched. Some
medicines (estrogen, nicotine) can pass through the skin, but
others cannot (insulin). This is because only fat-soluble
substances can enter the skin, not water-soluble ones.
Skin grows faster than any other organ and continues to grow
throughout our lives.