MASTERING Anatomy: Chapter 5

What is the importance of vitamin D synthesis in the epidermis? a. Vitamin D is required for the uptake of calcium from the diet, and thus is important to healthy bones. b. Vitamin D decreases the level of folate in light-skinned people. c. Vitamin D converts melanin to a soluble, thus usable, form. d. Vitamin D increases the iron content of blood, which makes bones stronger. e. Vitamin D decreases the risk from sunburn.

a

Which cell shown here produces pigments responsible for skin color? a. melanocyte b. tactile epithelial cell c. dendritic cell d. keratinocyte

a

Which of the following statements is true concerning skin pigmentation? a. Melanin may be yellow, brown, or black, which contributes to differences in skin pigmentation among different groups of people. b. Dark-skinned individuals have more melanocytes in their epidermis. c. In light-skinned people, melanin is digested by tyrosinase. d. Carotene is the most important of the pigments contributing to skin color.

a

What happens when someone gets a blister? a. Persistent friction causes a thickening of the epidermis. b. The dermis and epidermis are separated by a fluid-filled pocket. c. Cells shrink, but hold tight at many desmosomes. d. None of the listed responses is correct.

b

Apocrine sweat glands are distinguished by which of the following? a. They are a specialized form of a sebaceous gland. b. They are located over the entire surface of the body. c. They are confined to the genital, axillary, and anal regions. d. Their activity is highest during childhood.

c

As a certified nursing assistant, you are charged with watching the skin health of your patients. You should make sure that patients who have poor circulation and are confined to bed change their position____________. a. once a shift, every 8 hours b. every 4 to 6 hours c. at least every 2 hours d. at least every 15 minutes

c

What is true of both the stratum germinativum and stratum spinosum? a. these layers contain areolar connective tissue b. these layers contain blood vessels c. mitosis occurs in both layers d. they are dead e. they contain tactile epithelial cells (Merkel cells)

c

Which statement is FALSE concerning the skin's role in protection? a. The skin protects the body from invading microorganisms. b. The skin insulates the body's deeper organs. c. Cells in the dermis produce pigments that protect the skin from harmful ultraviolet radiation. d. The epidermis is waterproof, preventing unnecessary water loss.

c

As a dermatologist, you see a young man with a light complexion and heavy freckle development. You may want to caution him___________. a. to use sunscreen b. that people of fair complexion are more prone to sun damage c. to avoid excess sunlight d. All of the listed responses are correct.

d

Functions of keratin in the skin include __________. a. using receptor-mediated endocytosis to take up foreign proteins b. traveling to lymph nodes to initiate an immune response c. functioning as a touch receptor d. producing antibiotics and enzymes that detoxify harmful chemicals

d

Most aspects of skin aging are caused by "photoaging." Characteristics of photoaged skin include __________. a. thinner, but unwrinkled b. presence of lanugo c. presence of vernix caseosa d. liver spots and decreased amount of collagen in the dermis

d

Which of the following is a characteristic of the hypodermis? a. It consists only of adipose connective tissue. b. It is part of the skin. c. It anchors muscle to bone. d. It is distributed differently in males and females. e. It is a poor insulator.

d

Which of the following statements is correct regarding Melanocytes? They __________. a. are not present in the epidermis of light-skinned individuals b. are the only epidermal cells that contain melanin c. are one cell type that produces antibiotics that detoxify harmful chemicals d. respond to UV radiation by increasing production of melanin

d