Human Anatomy & Physiology Chap 5: Integumentary System
entire thickness of skin is burnt. skin is gray-white, cherry red or blackened. nerve endings destroyed
third degree burn
layer of 4-6 cell layers. keratinization begins. accumulate keratohyaline granules (producing keratin) and lamellar granules (contain glycolipid, aiding in water resistence). produce epidermal water barrier.
stratum granulosum
outer layer of the hair shaft. single layer of overlapping cells. most heavily keratinized layer
cuticle
proximal nail fold is the (eponychium)
cuticle
folds epidermis into dermis (in scalp, even into hypodermis). expands to form hair bulb
hair follicle
sensory nerve endings attached to hair bulb. aka root hair plexus
hair follicle receptor
dermal tissue providing nutrients through capillaries protruding into hair bulb
hair papilla
pinkish hue. oxygenated pigment in red blood cells in dermal capillaries.
hemoglobin
thickened region under free end of nail is
hyponychium
oil glands. simple branched alveolar. found everywhere except thick skin. secrete sebum. secrete lipids til they burst (holocrine glands). mostly as outgrowth of hair follicle
sebaceous glands
What lubricates the surface of the skin and hair, consists of cell fragments and fatty substances, and in excess may cause seborrhea?
sebum
epidermis and upper dermis burnt. redness, swelling, pain, blisters
second degree burn
Which of the following is not an epidermal derivative?: a) hair; b) sweat gland; c) sensory receptor; d) sebaceous gland.
sensory receptor
in hair, keratinization is complete in the
shaft
Amount of blood, pigments and oxygenation of blood determine
skin colour
The epidermis provides a physical barrier due largely to the presence of
keratin
Which epidermal cell type is most numerous?
keratinocyte
middle layer of hair shaft. absent in fine hair. large cells and air spaces. contains soft keratin.
medulla
pigment from reddish yellow to brownish black. passes from melanocytes to basal keratinocytes. only found in deeper layers of epidermis. productin stimulated by UV rays. protects DNA from UV rays
melanin
deepest layer of epidermal cells. single row of stem cells (stratum germinativum)
stratum basale
top layer (aka horny layer). anucleated (apopyosis: nucleus and organelles break down and plasma membrane thickens). 20 to 30 cell layers thick. made up of keratin and plasma membranes and glycolipid
stratum corneum
dendritic cells, macrophages, DNA
biological barriers
specialized sweat gland. secrete milk
mammary glands
clear layer in epidermis (only in thick skin). flat dead (too far from dermal capillaries to receive nutrients) keratinocytes. keratinocytes in tonofilaments made by keratohyaline granules cling to keratin filaments
stratum lucidum
cells also known as "prickle cells". (2nd layer). pre-keratin filaments attached to desmosomes
stratum spinosum
yellow to orange pigment. accumulates in stratum corneum and hypodermis
carotene
hard, dead keratinocytes make up
hair and nails
fine, pale body hair
vellus hair
expansion of hair follicle
hair bulb
network of blood vessels that nourish the the layers of the dermis
cutaneous plexus
The product of this type of sweat gland includes protein and lipid substances that become odiferous as a result of bacterial action:
apocrine gland
axillary and anogenital areas. (merocrine sweat gland). function sexual scent glands?
apocrine sweat glands
What causes a hair to stand up straight?
arrector pili muscle
modified apocrine sweat glands in external ear canal. secretion mixes with sebum to form cerum
ceruminous glands
skin secretions (acid mantle) and melanin
chemical barriers
separations or less dense regions of the collagen fiber bundles in the reticular layer. incisions made parallel to these lines heal more readily and gape less
cleavage lines
middle layer of hair shaft. many layers of flattened cells. surrounds medulla in thicker hair
cortex
Which cell functions as part of the immune system?
dendritic cell
more abundant sweat gland (palms, soles of feet, forehead). simple, coiled tubular gland. hypotonic filtrate. (merocrine sweat glands)
eccrine sweat glands
inner layer from invagination of epidermis regarding hair follicle
epithelial root sheath
The rule of nines is helpful clinically in estimating what?
extent of burn
only epidermis is burnt. redness swelling, pain
first degree burn
Skin surfaces that reflect tight dermal attachment to underlying tissues are called
flexure lines
body temp regulation, cutaneous sensation, metabolic functions,blood reservoir, excretion
functions of the Integumentary system
middle layer from thickened basal lamina regarding hair follicle
glassy membrane
the proximal and lateral borders of the nail are overlapped by skin folds called
nail folds
thickened portion of nail bed responsible for nail growth
nail matrix
layer of hair follicle from dermis. fibrous sheath
peripheral connective tissue sheath
layered keratinized skin cells
physical barrier
makes up 80% of thickness of the dermis. irregular, dense fibrous connective tissue cutaneous plexus lies between this and the hypodermis. matrix is adipose cells and collagen fibers
reticular layer
in hair, keratinization is ongoing in the
root
what are eccrine and apocrine
sweat glands
coarser, longer hair of eyebrows and scalp
terminal hair
The sensations of touch and pressure are picked up by receptors located in
the dermis
Which layer of the dermis is highly vascular, contains nerve endings that respond to stimuli, and is comprised largely of areolar connective tissue?
the papillary layer