The Integumentary System Skin The largest organ in

The Integumentary System

Skin • The largest organ in your body • Functions • • Covers the body and prevents water loss Protects the body from injury and infection Regulates body temperature Eliminates wastes (sweat) Produces vitamin D Gathers information about the environment Stores fat for fuel and insulation

Organs of the integumentary system The name is derived from the Latin integumentum, which means “a covering. ” l skin l hair l nails

Label and color the parts of the integumentary system finger nail

Prevents Water Loss l Skin prevents water from leaking out of your body.

Prevents Infection l Skins acts as a barrier to bacteria and viruses.

Eliminates Waste l Sweating eliminates dissolved waste from your body.

Gathers Information l Skin contains nerves that can feel pain or pressure.

Provide Vitamin D l With the help of sunlight, your skin produces vitamin D l Vitamin D is essential in calcium absorption from food

Maintains Homeostasis l Helps to keep the body temperature normal l Has blood vessels that tell the body when it is hot or cold ¡Hot – blood vessels get larger and sweating occurs ¡Cold – blood vessels constrict to keep blood in the body’s core

Layers of Skin l Skin consists of three main layers ¡epidermis ¡subcutaneous layer

Epidermis l Epidermis – the upper layer of skin where nails grow and where melanin is located. ¡ Every minute, 30, 000 - 40, 000 skin cells fall off ¡ 95% of your skin cells make new cells ¡ 5% make melanin ¡ More sun exposure = more melanin (tan)

l dermis - middle layer of skin that contains nerves, blood vessels, sweat glands, oil glands and hair follicles.

subcutaneous layer – acts as a fat storage to provide warmth and to absorb shock.

hair l Made of a strong, dead protein, called keratin. l Grows out of a tiny tube called a follicle. l Hair growth is caused by rapid mitosis in the follicle. l Hair follicles are everywhere except ¡lips ¡palms ¡soles

hair l Over 100, 000 follicles on the scalp. l Each follicle is attached to a gland that secretes sebum (oil). l Color is partially determined by melanin.

nails l Modified hair that grows from your cuticle. l Made of keratin. l No nerve endings. l Protects the end of fingers and toes l Takes 6 months to grow from cuticle to tip.

nails l Fingernails grow faster than toenails. l Nails grow faster on your dominant hand. l Nails DO NOT grow after death!

Body systems that work with the integumentary system; lrespiratory system to get oxygen and remove carbon dioxide. lcirculatory system to deliver oxygen. lexcretory system to eliminate waste.

l. The integumentary system is similar to the cell membrane in a cell. https: //www. youtube. com/watch? v=z 5 Vn. OS 9 Ke 3 g