integumentary accessory structures

what is hair made of

keratinized squamous epithelial cells

structures of hair

shaft, root, bulb, and papilla

what is the shaft

hair above skin surface

what is the root

remainder of hair within skin

what is the bulb

swelling at base of root

what is the papilla

projection of vascular tissue encased by bulb

what is the hair follicle

layer of epidermal tissue that anchors hair root

parts of the hair follicle

epithelial sheath (inner sheath and outer sheath)

dermal sheath

what is the hair matrix

region of dividing cells above papilla

what is the arrector pilli used for

thermoregulation and defense in animals

what does tension of arrector pili muscle cause

goosebumps

what does contraction of the arrector pili cause

piloerection

what type of muscle is the arrector pili

smooth muscle

structure in hair

medulla

cortes

cuticle

what is the medulla made of

core of loosely arranged cells

soft keratin

what is the cortex made of

several layers of compact keratinocytes

hard keratin

where is the site of pigmentation of hair

cortex

what is the cuticle made of

single layer of overlapping cells

hard keratin

what is the most highly keratinized region of hair

cuticle

what are split ends

damage to cuticle that exposes underlying layers

splitting or fraying of hair shaft

types of hair

lanugo

vellus

terminal

what is lanugo hair

unpigmented fetal hair

purpose of lanugo hair

insulation

what is vellus hair

fine body hair

what is terminal hair

eyebrows, eyelashes, scalp , facial, trunk, limb, armpit and public hair

what causes hair texture

related to cross-sectional shape of hair follicle

what gives color to terminal hair

pigment granules in cells of cortex

hair growth cycle

1. anagen

2. catagen

3. telogen

anagen phase

growth phase

hair follicle nourished by blood supply

catagen phase

transition phase

hair follicle detaches from blood supply

telogen

resting phase

without nourishment, hair dies and falls out

how does thin hair/baldness occur

hair sheds faster than new ones grow

what age does hair growth slow

around 50

how does pregnancy give longer and thicker hair

high estrogen extends anagen phase

increased blood flow and higher metabolism cause increased mitotic rate in matrix

telogen effluvium

abrupt hair thinning

why is there telogen effluvium postpartum

estrogen decline causes rapid shift to telogen phase

functions of hair

sensation, protection, and communication

function of nails

protection and object manipulation

parts of the nail

modified epidermis, nail plate, eponychium (cuticle) , nail bed (epidermis underlying nail plate), and nail matrix

what is the modified epidermis of the nail made of

hard keratin

parts of the nail plate

body (external) and root (internal)

site of nail growth

nail matrix

what is an ingrown nail

penetration of nail into surrounding tissue

what are the causes of ingrown nail

tight shoes

curved nail

injury

what can ingrown nails cause

pain

inflammation

infection

treatment for ingrown nail

lifting/partially removed nail

removing nail matrix

where are the glands of the integumentary system located

dermis

what are the glands of the integumentary system

groups of modified epithelial cells

what do exocrine glands release

non-hormonal secretions

what is released from glands of integumentary system

sweat and sebaceous

where are eccrine sweat glands located

all over body

where is sweat secreted in eccrine sweat glands

skin surface via ducts

purpose of eccrine gland

evaporative cooling

where are apocrine sweat glands located

only in axillary/genital regions

when are apocrine glands functions

after puberty

where is sweat secreted in apocrine glands and what does it cause

into hair follicles which causes odor due to bacterial ctivity

where are ceruminous sweat glands

lining of ear canal

what does ceruminous gland secrete

sebum and dead epithelial cells

purpose of cerumen

provides lubrication and protection

where are mammary sweat glands

within adipose tissue of breasts

purpose of mammary glands

secrete milk to nourish infant

who have mammary glands

both male and females

when do mammary glands develop

during pregnancy and lactation

regulatory function of the integumentary system

regulate:

body temp

fluid balance

waste management (through sweat)

blood reservoir

other functions of integumentary system

sensation, metabolic function, object manipulation, and communication

barrier function of integumentary system

chemical barrier, physical barrier, and biological barrier

where are sebaceous glands most present

face and scalp

where do sebaceous glands secrete into

hair follicles

when do sebaceous glands became active

after puberty

what do sebaceous glands secrete

sebum

functions of sebum

lubricates/waterproofs skin and hair

bactericidal properties

issues that can occur in sebaceous glands

high potential to get clogged

what are whiteheads

glands blocked by sebum and cellular debris

what is acne

bacterial infection of glands