Chapter 5 (the integumentary system)

The Integumentary System

the skin

What are the two membranes of the integumentary system?

Cutaneous membrane and accessory membrane

what is within the cutaneous membrane

epidermis and dermis

what layers are within the Dermis

papillary layer and reticular layer

what are the structures in accessory structures

Hairs, Nails, Exocrine glands, sensory receptors, and cutaneous plexus

Cutaneous plexus

a network of blood vessels

subcutaneous layer

separates the integument from the deep fascia.

epidermis

the outer layer of the skin is made of multiple layers of cells. Primarily being keratinocyte

stratum basale

attached to the basement membrane by hemidesmosomes. most cells here are basal cells.

stratum spinosum

composed of 8-10 layers of keratinocytes bound together by desmosomes. this is the start of keratin production.

stratum granulosum

composed of 3-5 layers of keratinocytes. this is where cells grow thinner and flatter.

stratum lucidum

found only in thick skin, separates corneum from the underlying layer, and is densely packed with dead cells filled with keratin.

stratum corneum

the outermost protective region with 15-30 layers of keratinized cells, dead cells still tightly connected by desmosomes.

list the order of the epidermis, starting from bottom to top.

Stratum basale, stratum spinosum, stratum granulosum, stratu, lucidum, and stratum corneum.

strata

Multiple layers of cells

thin skin

covers most of the body surface, four layers of strata

Thick skin

found in palms of hands and soles of feet, five layers of strata.

does thick skin contain stratum lucidum

yes

papillary layer

above the reticular layer and is composed of areolar tissue.

what does the papillary layer contain

Capillaries, lymphatic vessels, and sensory neurons.

reticular layer

interwoven meshwork of dense, irregular connective tissue.

what does the reticular layer contain

blood vessels, lymphatic vessels, nerve fibers, and accessory organs

what layer of the dermis is 1

papillary layer

what layer of the dermis is 2

reticular layer

epidermal ridges

formed from the deeper layer of the epidermis

dermal papillae

the superficial layer of the dermis

how do finger tips get ridges

an interaction between the epidermal ridges and dermal papillae

melanin

brown or black pigment that is produced by melanocytes

carotene

orange-yellow pigment from vegtables

hemoglobin

red pigment found in red blood cells

the more blood there is in your skin your skin will be

red

if there is less blood within your skin, your skin will be

pale

jaundice

yellowing of the skin due to a high level of bilirubin

bruising

discoloration of the skin due to broken blood vessels underneath the skin

when the bruising is red

o2 bound hemoglobin

when the bruising is blue

hemoglobin without O2

when the bruising is purple

mix of red and blue

when the bruising is green/ yellow

hemoglobin breaking down and processing

first degree burn

extends into the epidermis, causes redness in the skin

second-degree burn

extends into the dermis

third- degree burns

extends into the hypodermis, burns off nerves and is less painful

split-thickness graft

transfer of the epidermis and superficial portions of the dermis

full-thickness graft

transfer of the epidermis and both layers of the dermis

autograft

patients own undamaged skin

allograft

donor tissue

xenograft

animal graft

rule of nines

method of estimating the percentage of surface area affected by burns

terminal hairs

large, coarse, darkly pigmented

vellus hairs

smaller, shorter, delicate

where can you find terminal hairs

scalp, armpit, pubic region

where can you find vellus hairs

found on general body surface

on the hair was is 1

cuticle

on the hair was is 2

cortex

on the hair what is 3

medulla

on the hair what is 4

hair matrix

on the hair what is 5

hair papilla

on the hair what is 6

hair bulb

what is 1 on the hair follicle

hair shaft

what is 2 on the hair follicle

hair root

what is 3 on the hair follicle

root hair plexus

hair shaft

region of the hair beneath the skin surface

hair root

region of hair attached to the follicle wall (anchors the hair)

root hair plexus

sensory nerves surrounding the base follicle

medulla

a layer of daughter cells formed at the center of the matrix

cortex

intermediate layer that is deep into the cuticle

cuticle

daughter cells produced at the edges of the matrix form the surface of the hair

hair bulb

expanded base of hair follicle where hair growth occurs

hair papilla

connective tissue filled with blood vessels and nerves

hair matrix

actively diving basal cells in contact with hair papilla

keratinocyte

primary cell type in the epidermis

melanocytes

produces melanin

what are the two phases of hair growth

active phase and resting phase

active phase of hair growth

lasts 2-5 years, with hair growing 0.33 mm per day.

resting phase

the hair loss the attachment to the follicle and becomes a club hair. then, new hair formation begins

sudoriferous glands

sweat secretion

where can you find sudoriferous glands

around the surface of the skin

what are the two types of sudoriferous glands

Eccrine sweat glands and apocrine sweat glands

apocrine sweat glands

glands that metabolize excretions that produce the body odor smell.

where are apocrine sweat glands found

in the axillae, nipple, and pubic regions.

eccrine sweat glands

produces watery secretions with electrolytes

where is eccrine sweat glands found

most skin surfaces, the highest number are on palms and soles

sebaceous glands

secretion of sebum (oil)

sebum

a mixture of cholesterol, proteins, and electrolytes. lubricates the skin and hair shaft.

where is sebaceous glands located

most glands are connected to the hair follicles; few are connected to the skin's surface

what are the phases of integument repair

inflammation, migration, proliferation phase, scarring phase

inflammation phase

initial injury that causes bleeding and mast cell activation

migration phase

scabbing forms that the surface

proliferation phase

deeper portions of the clot dissolve. fibroblasts produce new collagen fibers

scaring phase

the scab is shed, and the epidermis is completely healed.