skin

Question 1

skin

Answer 1

Waterproof – Keeps water out when you’re in the shower or swimming.

✅ Stretchable – Moves with your body without tearing.

✅ Washable – You can clean it every day.

✅ Self-repairing – Small cuts and burns heal over time.

✅ Long-lasting – With care, your skin lasts your entire life.

Keeps good things in: Like water, nutrients, and body heat.

Keeps bad things out: Like bacteria, viruses, chemicals, and too much water.

Prevents dehydration and overheating: Without it, you’d lose water and heat too fast.

Protects against injury: It’s tough but flexible, so it takes hits and heals.

Question 2

what the integumentary system does.

Answer 2

The integumentary system, also called the integument (in-teg′u-ment), which simply means “covering,” performs a variety of functions; most, but not all, of which are protective (Table 4.1). It insulates and cushions the deeper body organs and protects the entire body from mechanical damage (bumps and cuts), chemical damage (such as from acids and bases), thermal damage (heat and cold), ultraviolet (UV) radiation (in sunlight), and microbes. The uppermost layer of the skin is hardened, to help prevent water loss from the body surface.

Question 3

mechanical stress

Answer 3

Keratin:

A tough, fibrous protein found in skin cells.

It strengthens and hardens the skin, making it a strong barrier against damage.

Receptors:

Pressure receptors and pain receptors are embedded in the skin.

They alert the nervous system when something might be harming your body (like a hard hit or injury).

Fat layer under the skin:

The fat beneath the skin cushions and protects deeper organs and tissues from bumps or shocks.

Question 4

protects us from acids and chemicals

Answer 4

Has relatively impermeable keratinized cells; contains pain receptors, which alert the nervous system to possible damage.

Question 5

microbe damage

Answer 5

Sweat and oil glands produce secretions that are acidic and contain chemicals.

This acidic environment makes it hard for bacteria and other microbes to grow on your skin.

Phagocytes are special immune cells in the skin that “eat” bacteria and harmful particles to keep you safe.

Question 6

protects body from uv

Answer 6

Melanin produced by melanocytes protects DNA from UV damage

Question 7

protects body from heat cold damage

Answer 7

Contains heat/cold/pain receptors.

Question 8

Desiccation (drying out)

Answer 8

Contains a water-resistant glycolipid and keratin.

Question 9

Aids in body temperature regulation (controlled by the nervous system)

Answer 9

Heat loss: By activating sweat glands and by allowing blood to flush into skin capillary beds so that heat can radiate from the skin surface.Heat retention: By not allowing blood to flush into skin capillary beds.

Question 10

Aids in excretion of urea and uric acid

Answer 10

Contained in perspiration produced by sweat glands

Question 11

Synthesizes vitamin D

Answer 11

Modified cholesterol molecules in skin converted to vitamin D in the presence of sunlight.

Question 12

futhermore

Answer 12

The skin’s rich capillary network and sweat glands (both controlled by the nervous system) play an important role in regulating heat loss from the body surface. The skin acts as a mini-excretory system; urea, salts, and water are lost when we sweat. The skin is also a chemical plant; it manufactures several proteins important to immunity and synthesizes vitamin D. (Modified cholesterol molecules in the skin are converted to vitamin D by sunlight.) The skin also produces acidic secretions, called the acid mantle, that protect against bacterial invasion.