Integument

Question 1

difference between thick and thin skin

Answer 1

stratum lucidum

Question 2

Stratum basale

Answer 2

single cell layer of keratinocytes and some melanocytes; mitotically active; desmosomes and hemidesmosomes

Question 3

Stratum spinosum

Answer 3

several cell layers thick; POLYHEDRAL keratinocytes with spiny processes; layer thickens with pressure (calluses)

Question 4

Stratum granulosum

Answer 4

thickest non-keratinized layer of epidermis; keratinocytes here have keratohyalin granules; irregular shaped and variable in size

Question 5

Keratohyalin granules

Answer 5

basophilic staining; cystine and histidine rich proteins; precursor to filaggrin, which helps assemble keratin into bundles

Question 6

Stratum corneum

Answer 6

anucleated cells; filled almost entirely with mature keratin; plasma membrane coated with extracellular layer of lipids (water barrier); constantly shed these cells

Question 7

Stratum lucidum

Answer 7

below corneum, above granulosum; poorly stained translucent bands of cells; no organelles or nuclei

Question 8

predominant cell type of epidermis; produces keratins (85% of the cells); participate in epidermal water barrier

Answer 8

Keratinocytes

Question 9

synthesizes intermediate keratin that is grouped into bundles known as tonofibrils

Answer 9

basal cells

Question 10

keratin synthesis and the glycolipid lamellar bodies are being synthesized

Answer 10

spinous cells

Question 11

discharge of lamellar bodies, keratohyalin granules present; filaggrin aggregates the tonofibrils; and the cells are now cornified

Answer 11

Granular cells

Question 12

Neural crest derived and scattered along the stratum basale; make melanin and transfers it to keratinocytes

Answer 12

Melanocytes

Question 13

one melanocyte maintains an association with a specific number of keratinocytes (1:36)

Answer 13

Epidermal-melanin unit

Question 14

Oxidation of tyrosine (tyrosinase; UV sensitive)

Answer 14

DOPA

Question 15

DOPA polymerized to

Answer 15

Melanin

Question 16

where does melanin production occur

Answer 16

premelanosomes which become melanosomes and extend into cell processes, transfer to keratinocytes (phagocytosis)

Question 17

pale cytoplasm with long processes; found in stratum spinous; APCs that migrate to a nearby lymph node to activate T cells

Answer 17

Langerhans Cells

Question 18

epidermal cells that function in cutaneous sensation of the fingertips; exist in stratum basale

Answer 18

Merkel Cells

Question 19

rare, highly aggressive skin cancer of Merkel cells

Answer 19

Merkel Cell Carcinoma (MCC)

Question 20

Dermal-epidermal junction

Answer 20

uneven boundary except in thinnest skin; dermal papillae (finger-like) project into epidermis, and epidermal protrusions of epidermal (rate) ridges; increase in size due to mechanical stress

Question 21

loose CT below epidermis; thin collagen fibers and elastic fibers; includes dermal papilla and ridges; VASCULATURE and NERVES

Answer 21

Papillary layer of dermis

Question 22

Deep to papillary layer; thicker and less cellular; irregular bundles of type I collagen and coarse elastic fibers; Langer’s lines

Answer 22

Reticular layer of dermis

Question 23

Langer’s lines

Answer 23

regular lines of tension

Question 24

adipose tissue, varies in thickness, every storage, arrestor pili muscles (for hair);

Answer 24

Hypodermis (subcutaneous fascia) not technically integument

Question 25

touch receptors for low frequency stimuli; tapered cylinder orient perpendicular to skin surface; found at junction in dermal papilla

Answer 25

Meissner’s Corpuscle

Question 26

large ovoid structured in deep dermis and hypodermic; fingertips, joints, periosteum, and internal organs; detect pressure or vibration; MYELINATED nerve ending in core surrounded by capsule

Answer 26

Pacinian Corpuscle

Question 27

terminate in stratum granulosum; lack CT; fine tough, heat, cold, and pain; surround most hair follicles (hair movement)

Answer 27

Free nerve endings

Question 28

many glands per follicle; face and scalp; produce sebum via holocene secretion (triglycerides and cholesterol); serum is discharged into the infundibulum (hair follicle) forming the pilosebaceous canal

Answer 28

Sebaceous Glands

Question 29

coiled glands distributed over body except lips and external genitalia; stratified cuboidal duct; myoepithelial cells facilitate expulsion of secretions; TEMP regulation

Answer 29

Eccrine (merocrine) sweat glands; CHOLINERGIC

Question 30

large-lumen, tubular glands; stratified cuboidal duct; uses merocrine secretion (protein, carbs, and ammonia) that is odorless unless mixed with bacteria (functional in puberty)

Answer 30

Apocrine sweat glands; ADRENERGIC