The Integumentary System Flashcards
The integumentary system is comprised of the largest organ in the human body – the skin – along with hair, nails, and accessory glands.
The integumentary system is in constant contact with the external environment and provides protection from and picks up signals about the body’s surroundings.
The primary organ of the integumentary system is the skin, or ____?
integument
The skin consists of 3 principal layers: ____, ____, and ____ ?
epidermis; dermis; hypodermis
The ____ is the outermost layer of the skin. It provides a barrier to infection from environmental pathogens and regulates the amount of water lost to the body’s surroundings. It is constantly being replaced with new skin cells.
epidermis
The ____, or middle layer of the skin, contains nerve endings, hair follicles, sweat and oil glands, and capillaries.
dermis
The ____ is the deepest layer of the skin and contains blood vessels and ____ (fat) tissues.
hypodermis; adipose
Sweat glands, or ____ glands, are responsible for the excretion of water and minerals from the body, in particular sodium, chloride, and magnesium.
sudoriferous
There are 2 types of sweat gland: ____ and ____?
eccrine; apocrine
____ glands appear all over the body and are the primary sweat glands of the body.
eccrine
____ are not active until puberty and are found in the armpits, nipples, and groin.
apocrine
Oil glands, or ____ glands, secrete sebum, a mixture of fats and proteins that prevents the skin and hair from drying out. They are found all over the body with the exception of the soles of the feet and palms of the hand.
sebaceous
Oil glands, or ____ glands, secrete sebum, a mixture of fats and proteins that prevents the skin and hair from drying out. They are found all over the body with the exception of the soles of the feet and palms of the hand.
sebaceous
____ are columns in the skin that have a large concentration of keratin-producing cells. These cells form the hair while adjacent melanin-producing cells give hair its pigmentation.
hair follicles
____, also made of keratin, are formed by keratin-producing cells at the ends of the fingers and toes.
nails
____, also made of keratin, are formed by keratin-producing cells at the ends of the fingers and toes.
nails
When sensory nerves in the skin indicate that the body is entering a state of ____, meaning that the body temperature is elevated above normal, the integumentary system helps to reduce body temperature through sweat and vasodilation of the blood vessels.
hyperthermia
The sudoriferous glands deliver water to the skin in the form of sweat, which evaporates from the skin’s surface. As the water evaporates, it absorbs and carries away heat with it, cooling the body.
Dilated blood vessels in the dermis allow more blood to get near the surface of the skin, carrying excess heat from the body’s core. This heat is then released to the external environment as thermal radiation.
The sudoriferous glands deliver water to the skin in the form of sweat, which evaporates from the skin’s surface. As the water evaporates, it absorbs and carries away heat with it, cooling the body.
Dilated blood vessels in the dermis allow more blood to get near the surface of the skin, carrying excess heat from the body’s core. This heat is then released to the external environment as thermal radiation.
When the body enters a state of ____, meaning that body temperature drops below normal, the integumentary system prevents heat loss.
hypothermia
Blood vessels constrict to reduce the amount of blood flow through the skin, limiting the amount of heat lost to the external environment through radiation. The muscles of the hair follicles contract to lift the hair upright, trapping air against the surface of the skin and helping to insulate the body.
This is often referred to as “goose bumps” when the contracted muscles can be seen as bumps beneath the skin.
