Introduction to Dermatology and Epidermis

Question 1

List the layers of dermis from outside to inside.

Answer 1

Epidermis, papillary dermis, reticular dermis, and subcutaneous fat.

Question 2

What are the layers of tissue within the epidermis?

Answer 2

Stratum corneum, stratum granulosum, stratum spinosum, and stratum basalis

Question 3

List and describe some of the functions of the skin.

Answer 3

Barrier (to physical things, light, and pathogens), vitamin D synthesis, water retention, thermoregulation, and sensation

Question 4

What is Fitzpatrick I?

Answer 4

Never tans; always burns

Question 5

What are the two types of melanin?

Answer 5

Eumelanin (black/brown) and pheomelanin (yellow/red-brown)

Question 6

How are dark and light skin types different?

Answer 6

In darker skin, melanosomes are larger and distributed throughout the cytoplasm, while in lighter skin melanosomes are smaller and usually near the nucleus

Question 7

Albinism is due to a ________.

Answer 7

defect in the tyrosinase gene involved in melanin production

Question 8

Explain the pathology of vitiligo.

Answer 8

Vitiligo is an autoimmune disorder in which the body attacks melanocytes, resulting in acquired depigmentation.

Question 9

Vitamin D can come from _____.

Answer 9

the diet or from UVB and 7-dehydrocholesterol (in the skin)

Question 10

What connects the epidermis to the dermis?

Answer 10

Hemidesmosomes (defects of which can cause bullous pemphigoid)

Question 11

The genetic defect in recessive dystrophic epidermolysis bullosa is ________.

Answer 11

defect in collagen VII

Question 12

The genetic defect in junctional epidermolysis bullosa is ______.

Answer 12

mutations in laminin V

Question 13

Stratum spinosum cells are held together with __________.

Answer 13

desmosomes (which is why they appear spiny)

Question 14

There are two main disorders of stratum spinosum desmosomes: ________.

Answer 14

pemphigus vulgaris (acquired autoimmune) and epidermolysis bullosa simplex (genetic)

Question 15

The stratum lucidum is found deep to _______.

Answer 15

thick skin (between the corneum and granulosum strata)

Question 16

The medical term for “red all over” is ______.

Answer 16

erythroderma

Question 17

Which is denser, papillary or reticular dermis?

Answer 17

reticular (it is also deeper)

Question 18

How do melanocytes transport melanin, and to what cells?

Answer 18

Through dendrites, to keratinocytes

Question 19

What are dendritic cells in the skin called?

Answer 19

Langerhans cells

Question 20

Explain the difference between eccrine and apocrine glands?

Answer 20

Apocrine glands are specialized and are found in the pubic, axillary, and perianal regions, while eccrine glands are sweat glands and are found everywhere except the lips, under the nail beds, and on the glans of the penis and the clitoris.

Question 21

The peripheral parts of the extremities and fingers is called the ____ region.

Answer 21

acral

Question 22

Describe the pathophysiology of pemphigus vulgaris.

Answer 22

Autoimmune disorder in which antibodies attack the desmosomes that adhere stratum spinosum cells, leading to intraepithelial blisters.

Question 23

In which layer of the epidermis does water retention occur, and how?

Answer 23

Filaggrin breaks down in the stratum cornea and retains water.

Question 24

What are flat lesions called?

Answer 24

Macules, and patches when they are larger than 1.0 cm

Question 25

What are raised lesions called?

Answer 25

Papules, and plaques when larger than 1.0 cm

Question 26

_____ are larger forms of vesicles.

Answer 26

Bulla

Question 27

Crusts are _____.

Answer 27

dried serum, blood, or pus

Question 28

What are telangiectasias?

Answer 28

Visible dilations of subcutaneous blood vessels