Chapter 1: Introduction to dermpathologic diagnosis

Question 1

Merkel cells are most heavily concentrated in

Answer 1

with high hair density and in glabrous epithelium of the digits, lips, regions of the oral cavity, and the outer root sheath of the hair follicle.

Question 2

Merkel cells also express neuroendocrine markers such as

Answer 2

chromogranin A and
synaptophysin

Question 3

Langerhans cells are bone marrow-derived, dendritic, antigen-presenting cells that appear in the epidermis by 7 weeks of gestation, as documented by their positive staining for _____

Answer 3

adenosine triphosphatase (ATPase)

Question 4

. Several enzyme histochemical stains have historically been used to identify Langerhans cells and to differentiate them from melanocytes. These include:

Answer 4

ATPase , aminopeptidase ,
HLA-DR antigen and S100 protein

Question 5

____is an inconspicuous structure of enormous functional significance, bonding together the protective epidermal layer and adnexal structures with the adjacent dermis.

Answer 5

basement membrane I

Question 6

Beneath the plasma membrane of the basal cells, a rather electron-lucent zone called the ____ separates the trilaminar plasma membrane, about 8 nm wide, from the more electron-dense component of the basement membrane, or _____

Answer 6

lamina lucida;
lamina densa

Question 7

the basal cell layer lying on top of the dermal hair papilla

Answer 7

pigment matrix region

Question 8

Part of the hair follicle extending from the base of the follicle to the insertion of the arrector pili muscle

Answer 8

lower portion

Question 9

Part of the hair follicle:

a rather short section, extending from the insertion of the arrector pili to the entrance of the sebaceous duct

Answer 9

middle portion, or isthmus

Question 10

Part of the hair follicle:

extending from the entrance of the sebaceous duct to the follicular orifice

Answer 10

upper portion, or infundibulum,

Question 11

anagen stage—the phase of active growth—lasts at least

Answer 11

3 years

Question 12

catagen—the phase of regression—lasts about

Answer 12

3 weeks

Question 13

telogen—the resting period

Answer 13

—lasts about 3 months

Question 14

The outermost layer of the inner root sheath, the ____, keratinizes first, thus establishing a firm coat around the soft central parts.

Answer 14

Henle layer

Question 15

The inner root sheath is composed of three concentric layers; from the inside to the outside, Namely:

Answer 15

inner root sheath cuticle, the Huxley layer, and the Henle layer

Question 16

the three concentric layers of inner root sheath DO NOT CONTAIN MELANIN: True or False

Answer 16

True