Chapter 6: Integumentary System

Question 1

What are the functions of the integumentary system?

Answer 1

• Resistance to trauma (keratin, acid mantle)
• Waterproofing
• UV radiation
• Against harmful chemicals
• Vitamin D synthesis
• Thermoregulation
• Transdermal absorption
• Sensation

Question 2

What determines skin color?

Answer 2

The production of melanin by melanocytes, accumulates in the stratum basale and spinosum. We all have the same number of melanocytes, but the difference in production of melanin gives us different skin colors.

Question 3

What is eumelanin?

Answer 3

Responsible for brownish-black skin color.

Question 4

What is pheomelanin?

Answer 4

Responsible for red-yellow sulfur containing pigment

Question 5

What is the difference between dark and light-skinned people in terms of their epidermal cells?

Answer 5

Dark-skinned people have melanin granules more spread out and it breaks down more slowly. Light-skinned people have melanin clumped more near nuclei of keratinocytes, and it breaks down quicker. Hemoglobin is also seen more in light skin, giving a reddish appearance.

Question 6

What is carotene?

Answer 6

Yellow pigment acquired from egg yolks and orange vegetables. It concentrates in corneum and subcutaneous fat

Question 7

Describe basal cell carcinoma and its frequency and outcomes.

Answer 7

This is the most common and least dangerous type since it rarely metastasizes. Lesion is small, shiny bump with central depression and beaded edges. Forms in stratum basale

Question 8

Describe squamous cell carcinoma and its frequency and outcomes.

Answer 8

Forms in stratum spinosum. Lesions usually on scalp, ears, lower lip, back of hand. Have raised, reddened, scaly appearance later forming concave ulcer. Chance of recovery is good with early detection and surgical removal. If not, can metastasize to lymph nodes, lethal

Question 9

Describe malignant melanoma and its frequency and outcomes.

Answer 9

This arises from melanocytes and is usually preexisting mole. This is more rare and the most deadly. If caught early can be treated surgically but metastasizes rapidly and is unresponsive to chemo, fatal

Question 10

What is the ABCD rule for detecting skin cancer?

Answer 10

• Asymmetry
• Border
• Color
• Diameter

Question 11

First-degree burn

Answer 11

Partial thickness burn; involves only the epidermis. Sunburns.

Question 12

Second-degree burn

Answer 12

Partial thickness burn; involves the epidermis and part of dermis (leaves part of the dermis intact).

Question 13

Third-degree burn

Answer 13

Full thickness burn; the epidermis and all of the dermis, and often some deeper tissues are destroyed. Often requires skin grafts.