Integument

Question 1

Two layers of epidermis?

Answer 1

Papillary and reticular layer

Question 2

What kind of excretion do eccrine sweat glands do?

Answer 2

Merocrine (exocytosis). They are called eccrine sweat glands

Question 3

What organs don’t have sweat glands?

Answer 3

the glans penis, the inner surface of the foreskin, the clitoris, and the labia minora.

Question 4

What kind of excretion do apocrine sweat glands do?

Answer 4

Merocrine (exocytosis)

Question 5

What is merocrine secretion?

Answer 5

Merocrine, or eccrine, secretion occurs by exocytosis. This is the mode of secretion of both eccrine and apocrine glands, which can be very confusing.

Question 6

What is apocrine secretion?

Answer 6

Apocrine secretion occurs when a portion of the plasma membrane containing the secretion buds off from the cell. This is the mode of secretion of the mammary glands and mucous-producing cells, but not the apocrine sweat glands.

Question 7

What is holocrine secretion?

Answer 7

Holocrine secretion occurs when the entire cell disintegrates in order to release its secretion. Sebaceous glands exhibit holocrine secretion, as the sebum is released with remnants of dead cells.

Question 8

Name the four layers of the epidermis and the state of keratin associated with each.

Answer 8

Stratum basale, Stratum spinosum - cytokeratin, Stratum granulosum - keratohyaline, Stratum corneum - keratin

Question 9

What are the important differences between sebaceous glands, eccrine sweat glands, and apocrine sweat glands?

Answer 9

Sebaceous glands produce sebum to protect hair. Eccrine sweat glands produce a thin, watery sweat all over the skin, whereas apocrine sweat glands are much larger and produce a thicker sweat in select areas. Sebaceous glands undergo holocrine secretion; both sweat glands undergo eccrine secretion.

Question 10

What is the structure of the mammary gland, and what key differences do you expect to see between active and inactive mammary tissue?

Answer 10

Acini make up lobes, which empty into the lactiferous sinuses via the lactiferous ducts. Inactive tissue will not be producing much milk; the lumina will be empty and the epithelial cells will be smaller and have fewer visible lipid droplets. Active tissue would have abundant lipid droplets, visible milk, and taller cells.

Question 11

Name the three types of exocrine secretion, their key characteristics, and an example of a cell that demonstrates each one.

Answer 11

Holocrine secretion involves the destruction of the cell. Sebaceous glands undergo holocrine secretion. Eccrine secretion involves exocytosis of the material. An example is the eccrine or apocrine sweat glands. Apocrine secretion involves secretion of a portion of membrane with the secretion, which occurs in mammary glands and mucous cells.

Question 12

In what cell type does most of the melanin reside?

Answer 12

Keratinocytes

Question 13

Why is a tattoo permanent?

Answer 13

The ink of the tattoo is in the dermal layer which doesn’t not get turned over like the cells in the epidermal layer.

Question 14

Differences in psoriatic skin and normal skin?

Answer 14

Elongation of the rete ridges and mitotic cells above the basal layer that is a sign of increased cell turnover in the epidermis. Increased number of cells in the dermal region that is a sign of an inflammatory response.

Question 15

Where do you find keratohyaline?

Answer 15

Stratum granulosum

Question 16

What are the characteristics of the stratum granulosum?

Answer 16

Keratohyaline. Lamellar bodies. Keratin 2e and 9.

Question 17

What do Langerhans cells do?

Answer 17

Antigen presenting

Question 18

Espression of keratin in each layer?

Answer 18

Basale: 5 an 14; spinosum: 1 and 10; granulosum: 2e and 9

Question 19

When do lamellar bodies appear? When are they extruded?

Answer 19

Appear in spinosum and granulosum, release during transition to lucidum and corneum

Question 20

What makes up the cornified cell envelope?

Answer 20

Aggregates of keratins and filaggrin and complex of involucrin, small proline-rich proteins, and loricrin, cross-linked by transglutaminase K

Question 21

What cell components are the targets of autoantibodies causing blistering diseases?

Answer 21

Keratine filaments (tonofilaments)

Question 22

Meissner corpuscle

Answer 22

Dermal papilla. Tactile receptor

Question 23

Merkel cell

Answer 23

Basal layer of epidermis. Neural crest-derived. Tactile receptor.

Question 24

Free nerve endings

Answer 24

No myelin or schwann cells. Pain and temperature. Epidermis and corneal epithelijm

Question 25

Raffini end organ

Answer 25

Stretching. Skin and joint capsule.

Question 26

Pacinian corpuscle

Answer 26

Pressure. Hypodermis and deep fascia

Question 27

Peritrichial nerve ending.

Answer 27

wrapped around hair. stimulated by hair movement.

Question 28

What is different in the skin in cystic fibrosis?

Answer 28

High salt concentration in sweat. The cystic fibrosis transmembrane conductance regulator channel is malformed and Na and Cl are not able to be reabsorbed.

Question 29

Racial differences in human skin pigmentation are due to

Answer 29

differences in melanin granule number, size, and turnover

Question 30

Mechanism of melanin secretion

Answer 30

merocrine

Question 31

Most of the melanin in the strutum malpighi layer is in the

Answer 31

keratinocyte

Question 32

What does MITF do?

Answer 32

Melanocyte cell cycle arrest and stimulates the expression of genes encoding proteins involved in melanin production.

Question 33

What are the ABCDE of malignant melanoma?

Answer 33

Asymmetry
Border irregularity
Color (non-uniform pigment)
Diameter (>6mm)
Evolving