HW - ch 5

Since the epidermis is avascular, how do the epidermal cells obtain their nutrients?

From the blood vessels in the adjacent dermis

What is the function of melanin?

It protects DNA from the damaging effects of ultraviolet radiation.

Open onto the surface of the skin and produce most of the sweat for the body; regulation of body temperature

Merocrine sweat glands, or eccrine sweat glands

How would you explain to your roommate, who has never taken an A&P class, why it is that a superficial cut hurts less than a deep cut?

Nerve fibers are located in the reticular layer of the dermis of the skin.

The hypodermis

is quite elastic.

The protein that contributes to many of the skin's protective qualities is called ________.

keratin

The pale crescent area of the nail is called the

lunula

The most severe type of skin cancer is most likely to develop from

melanocytes

When the arrector pili muscles contract,

"goose bumps" are formed.

Epidermal cells synthesize this vitamin when exposed to sunlight.

vitamin D3

Choose the correct order of the cell layers, or strata, in a section of thick skin, from the basement membrane toward the free surface (deep to superficial). 1. stratum lucidum 2. stratum basale 3. stratum corneum 4. stratum granulosum 5. stratum spinosum

2, 5, 4, 1, 3

Which of the following statements is NOT TRUE regarding skin color? - A person's skin color depends on the number of melanocytes present in the epidermis. - UV radiation increases melanin production. - Blood vessels in the dermis affect skin color. - Both carotene and melanin are pigments that affect skin color.

A person's skin color depends on the number of melanocytes present in the epidermis.

Which of the following structures are composed of dead cells?

All of the structures are composed of dead cells.

In which of the epidermal layers are the cells undergoing mitosis?

Stratum basale

Why would the ink of permanent tattoos be deposited in the dermis, and not the epidermis of the skin?

The epidermis is continually replaced by new cells as old cells are shed.

The condition that results from clogged sebaceous glands is

acne

The dermis is composed largely of ________.

dense irregular connective

When the body is overheated, the skin responds by

dilating blood vessels.

The deepest layer of cells in the epidermis is the cells of the ________.

stratum basale

thickest layer of the epidermis and is the most superficial layer of the epidermis.

stratum corneum

The epidermal layer whose cells have stopped dividing and started to produce large amounts of keratin is the

stratum granulosum

Modified and specialized sweat glands that produce milk are called ________ glands.

mammary

Merocrine sweat glands

respond primarily to elevated body temperature

Which gland is responsible for odorous secretions concentrated in the armpits and groin?

apocrine sweat gland