Derm Histo

Question 1

What kind of epithelium lines the duct of eccrine sweat glands?

Answer 1

stratified cuboidal

Question 2

Which layer of the epidermis secretes tonofilaments? In which layer do the tonofilaments become tonofibrils?

Answer 2

stratum basale, stratum spinosum

Question 2

What do Pacinian corpusles detect? What makes up the inner core? Outer core?

Answer 2

vibratory pressure and mechanical stimuli? Inner = Schwann cells, Outer = endoneurium

Question 3

What kind of cells make up the stratum germinativum?

Answer 3

columnar

Question 4

How are the cells of the stratum spinsoum connected to one another? What effect does this have on their shape?

Answer 4

by desmosomes? It gives them a spiny look when the cells shrink for histo prep since the connections remain but the cell shrinks

Question 4

What causes thermoregulatory sweating? Emotional sweating?

Answer 4

cholinergic and adrenergic stimulation of eccrine glands, respectively

Question 5

Which layer of the epidermis contains high levels of keratohyalin granules?

Answer 5

Stratum granulosum

Question 5

What are “Langer’s lines”?

Answer 5

They are lines of tension formed via the Type I collagen and elastin present in the reticular dermal layer

Question 5

Where will you find melanocytes?

Answer 5

stratum basale

Question 6

What is pigment donation?

Answer 6

When the tips of the melanocytes containing melanin are phagocytosed by keratinocytes

Question 7

What epithelium lines the duct of apocrine sweat glands?

Answer 7

stratified cuboidal

Question 9

Which structures are responsible for fingerprints?

Answer 9

dermal papillae

Question 9

What structures are notable for forming the lipid envelope of skin cells?

Answer 9

lamellar bodies secreted to the outside of the cell

Question 11

What gives the stratum granulosum its basophilic color?

Answer 11

keratohyaline granules

Question 12

T/F: the epidermis is vascularized

Answer 12

false that is the point of the dermal papillae, they extend up to the abutting epidermis and from there nutrients travel via diffusion

Question 13

T/F: nuclei are present in the stratum lucidum of thin skin but not thick skin

Answer 13

false, first of all the stratum lucidum is only ever present in thick skin, second there are no nuclei in the stratum lucidum = the cells are dead

Question 14

Which sweat glands are located “everywhere”? Where are they not located?

Answer 14

eccrine (merocrine secretion); rubor labii and external genitalia

Question 15

Mechanism of secretion of sebaceous glands

Answer 15

holocrine

Question 16

Melanin production is increased by what hormone? What parent molecule does this come from?

Answer 16

MSH, comes from POMC so associated with ACTH? recall this is why there is hyperpigmentation in Addison’s dz

Question 18

What are the “spines” in the stratum spinosum?

Answer 18

Desmosomes

Question 19

what is the name of the edge of skin covering the nail root?

Answer 19

eponychium

Question 20

Where will you find the matrix cells of the hair follicle?

Answer 20

around the dermal papilla

Question 21

What collagen fibers make up the dermal papillae? What sensory nerve endings might you find in here? Myelinated or unmyelinated?

Answer 21

Type I and II; Meissner’s corpuscles, myelinated? the only unmyelinated ones are C fibers

Question 22

What are the 3 cell types of the secretory segment of an eccrine sweat gland?

Answer 22

clear cells to secrete the watery component, dark cells to secrete protein, and myoepithelial cells to push it all along

Question 23

What connects the epidermis to the dermis?

Answer 23

hemidesmosomes

Question 24

what connects the epidermis to the dermis? What connects the cells of the stratum spinosum to one another?

Answer 24

hemidesmosomes, desmosomes

Question 26

What do Merkel cells detect? Myelinated or unmyelinated?

Answer 26

pressure? Myelinated the only ones not myelinated are C fibers

Question 27

Where will you find Merkel Cells?

Answer 27

in the stratum basale

Question 28

Langerhans cells come from what parent cell (ultimately)?

Answer 28

CD34 pluripotent hematopoietic stem cell

Question 29

What layer of the nail is the formative layer?

Answer 29

nail matrix

Question 30

How can you differentiate a Langerhans cell from a melanocyte?

Answer 30

Melanocytes are located in the stratum basale and Langerhans cells are located in the stratum spinosum

Question 31

How are Langerhans cells connected to the keratinocytes?

Answer 31

They arent

Question 32

Name 2 modified sebaceous glands

Answer 32

Glands of Moll on the eyelid and Ceruminous glands (wax) of ear canal

Question 33

What is contained in the invagination of the inferior segment of the hair follicle? Why is it important?

Answer 33

dermal papillae, this provides nutrients to the growing hair

Question 34

Where will you find Meissner's corpuscles?

Answer 34

IN THE DERMAL PAPILLAE

Question 35

Which layer is the skin-nail junction?

Answer 35

hyponychium

Question 37

Where is the melanin in a melanocyte contained?

Answer 37

melanosomes

Question 38

If you were to poke a hole in the skin, why would it be elliptical rather than round?

Answer 38

The Langer's lines in the reticular layer of the dermis form lines of tension

Question 39

How are the melanocytes attached to keratinocytes?

Answer 39

They arent, the migrated in from neural crest and just kind of chill there

Question 40

What kind of muscle makes up the arrector pili muscles?

Answer 40

smooth muscle

Question 41

How is the lumen of apocrine and eccrine glands different?

Answer 41

lumen of apocrine are wider

Question 42

What are the 3 layers of the internal root sheath?

Answer 42

outer Henles layer of cuboidal cells, then huxley's layer which is 1-2 layers of squamous cells, on the inside is the cuticle of the hair shaft

Question 43

What 2 keratohyalin granules are present in the stratum granulosum?

Answer 43

trichohyalin and filaggrin