chapter 5: integumentary system

Question 1

what are 2 basic structures of the skin?

Answer 1

epidermis and dermis
they are cemented together

Question 2

which layer is immediately deep to the dermis?

Answer 2

subcutaneous layer/ hypodermis

Question 3

what is subcutaneous layer primarily composed of?

Answer 3

adipose tissue

Question 4

what is the structure of the epidermis?

Answer 4

keratinized stratified squamous epithelium

Question 5

Name the 4 cells of the epidermis

Answer 5

keratinocytes
melanocytes
dendritic
tactical epithelial

Question 6

describe keratinocytes

Answer 6

produce keratin(fibrous protein that gives epidermis durability and protective capabilities)

Question 7

describe melanocytes

Answer 7

spidery black cells that produce brown-black pigments called melanin

Question 8

dendritic cells

Answer 8

aka langerhans cells

arise from bone marrow and migrate to epidermis

ingest foreign substances and play key role in activating immune system

Question 9

tactile epithelial cells

Answer 9

spikey hemispheres that form sensitive touch receptors located at epidermal-dermal junction

Question 10

what are the 4 (5) layers of epidermis?

Answer 10

stratum corneum (horny layer)
(stratum lucidum (clear layer))
stratum granulosum (granular layer)
stratum spinosum (spiny layer)
stratum basale (basal layer)

Question 11

describe stratum corneum

Answer 11

aka horny layer

has 20-30 dead, scalelike, keratinocytes

constantly being exfoliated and replaced

Question 12

describe stratum lucidum

Answer 12

aka clear layer

present only on thick skin, palm of hand sole of feet

Question 13

describe stratum granulosum (2)

Answer 13

aka granular layer
has abundant granules
1. lamella granules: has waterproofing glycolipids secreted into extracellular space
2. keratinohyaline granules: helps form keratin in superficiaal layers

Question 14

describe stratum spinosum

Answer 14

aka spiny layer

thick weblike bundles of intermediate filaments made of pre keratin protein
called spiky bc when the tissue is prepared, cells shrink, but desmosomes hold tight to adjacent cells.

receives adequate nourishment from diffusion of nutrients from dermis

Question 15

describe stratum basale

Answer 15

aka basal layer

single row of cells immediately above dermis

constantly undergoing mitosis to form new cells

10-25% are melanocytes

receives adequate nourishment from diffusion of nutrients from dermis

Question 16

what are the 2 parts of the dermis?
describe them

Answer 16

1. papillary dermis: superficial region
   made of areolar connective tissue
   dermal papillae attach to epidermis above (hence fingerprints)
2. reticular dermis: deepest skin layer
   has irregular dense tissue
   contains many artieries and veins.

Question 17

carotene

Answer 17

yellow-orange pigment present in stratum corneum and adipose tissue

Question 18

cyanotosis

Answer 18

bluish cast when blood is poorly oxygenated, like in asphyxiation

Question 19

jaundice

Answer 19

tissues become yellowed, diagnosis of liver disease

Question 20

addisons disease

Answer 20

bronzing of the skin, adrenal cortex is hypoactive

Question 21

name all nail parts (9)

Answer 21

nail plate
free edge
hyponychium
nail root
nail folds
eponychium
nail bed
nail matrix
lunule

Question 22

primary hair regions (2)

Answer 22

1. hair shaft: region projecting from surface of skin
2. hair root: beneath the surface and is embedded in the hair follicle

Question 23

layers of hair shaft and hair root (3)

Answer 23

medulla: center
cortex: surrounds medulla
cuticle: protective

Question 24

hair follicle

Answer 24

in both epidermal and dermal

epithelial root sheath is enclosed by basement membrane, glassy membrane peripheral connective tissue sheath (essentially dermal tissue)

Question 25

hair papilla

Answer 25

nipple of dermal tissue protruding into the hair bulb from peripheral connective tissue sheath and provides nutrition to growing hair

Question 26

hair matrix

Answer 26

layer of actively dividing epithelial cells

Question 27

arrector pili muscle

Answer 27

small bands of smooth muscle cells that connect each hair follicle to papillary layer of dermis

Question 28

types of cutaneous glands (2)

Answer 28

sebaceous (oil) glands
sweat (sudoriferious) glands

Question 29

sebaceous oil glands are..

Answer 29

found all over body except palms and soles

mix of oil substances and fragmented cells that keep skin soft (natural skin cream)

Question 30

describe sweat (sudoriferous) glands

Answer 30

are exocrine glands

all over skin

outlets are called pores

Question 31

types of sweat (sudoriferous) glands

Answer 31

eccrine sweat glands: all over body
made of water, salts and urea
important in heat regulation system

apocrine sweat gland: pound in axillary and genital area
secrete water, salts, urea along with protein and fatty substance,
excellent nutrient medium