ch. 5, 6, 7, 8, 9 Flashcards
2 major components of the integumentary system
cutaneous membrane
accessory structures
epidermis and dermis (and hypodermis)
cutaneous membrane
hair, nails, sebaceous glands and sweat glands
accessory structures
protect of underlying tissues and organs excrete salts, h2o, and organic wastes by glands help maintain body temp produce melanin product keratin make vitamin D store lipids detect touch, pressure, pain and temp
fx of skin
what type of tissue makes up the epidermis
stratified squamous epith
what is the vascularity of the epidermis
avascular- but deepest cells rely on diffusion of nutrients and o2 from capillaries within dermis
4 layers of the epidermis
stratum corneum
stratum granulosum
stratum spinosum
stratum basale
on top
15-30 layers of cells
dead cells and are easily rubbed away
stratum corneum
3-5 layers of cells - thinner and flatter with keratin
stratum granulosum
thick layer (8-10 layers of cells)
stratum spinosum
what is stratum basale also known as
germinativum
deepest layer- next to basement membrane
tightly bound to dermis
much mitosis here via stem cells
stratum basale
what skin has 5 layers of skin
stratum granulosum
how long do skin cells live
7-10 days
how long does skin take to move through its life cycle
dead cells stay in stratum corner for additional 2 weeks before they are shed or washed away
tough fibrous proteins
keratin
where is keratin found
within stratum granulosum
basic structural component of hair and nails
keratin
where is keratin made
stratum corner cells are keratinized-have protective, hardened, superficial layer of cells filled w keratin (water resistant)
another word for keratinized
cornified
2 pigments naturally found in the epidermis
carotene
melanin
yellow orange pigment found in orange vegetables
can accumulate in epidermal cells and hypodermic
carotene
what color is melanin
brown, yellow-brown, or black pigment
what cells produce melanin
melanocytes in stratum basale
melanosomes and these travel up epidermis
package it in vesicles
pale skin?
melanosomes don’t travel very far up
darker skin?
melanosomes are larger and travel farther up
what is the difference in skin pigmentation
no difference in number of melanocytes just depends on levels of how much melanin is made
fx. protect deeper cells from UV radiation; melanocytes increase their activity in response to UV exposure
melanin
how does the fx of melanin relate to tanning
melanin protects us from UV rays until it can no longer protect us, causing us to burn
blod contains RBC’s filled with hemoglobin which binds and transports o2
dermal circulation
lots of o2 in dermal circulation
hemoglobin in bright red and skin appears reddish
drop in o2
hemoglobin is darker red and skin appears pale and/or bluish (cyanosis)
what is cyanosis
when skin appears blue
if dermal blood vessels dilated?
appear flushed and occurs with increase body temp to assist body to lose excess heat
if dermal blood vessels constricted
appear pale and occurs with decrease body temp to decrease heat loss
what vitamin is produced in the skin
vitamin D
vitamin d is produced when the skin is exposed to what
UV radiation
hormone that is needed for the normal absorption of calcium and phosphorus by the small intestine; needed for bone maintenance and growth
fx. of vitamin d
epidermal cells of stratum spinosum and stratum basal make what
vitamin d
besides the skin producing vitamin d where else is vitamin d obtained
obtained from diet
2 types of tissues that make up the dermis
areolar tissue
dense irregular conn tissue
2 types of fibers found in the dermis
collagen fibers
elastic fibers
very strong and resist stretching
collagen fibers
permit stretching and recoil
elastic fibers
what causes wrinkles and sagging skin
aging, hormones and increased UV radiation exposure permanently decreases amount of elastin in dermis
supply blood to both dermis and hypodermic
dermal blood vessels
fx. supply nutrients and o2 to dermis, deep cells if epidermis and hypodermis
helps regulate body temp
dermal blood vessels
3 types of sensory receptors found in the skin
sensory neurons
tactile (meissner) corpuscle
laminated (pacinian) corpuscle
for pain, touch, and temp
sensory neurons
for light touch; most abundant in eyelids, lips, fingertips, nips, and external genitalia
meissner corpuscle
for deep pressure
pacinian corpuscle
another name for hypodermis
subcutaneous layer
consists of blood vessels
areolar tissue
adipose tissue
components of hypodermis
fx. extra insulation, help decrease heat loss, energy reserve, shock absorber
hypodermis
where on the skin hair is not found
sides and soles of feet, palms of hands, sides of fingers and toes, lips and portions of external genitalia
where is 75% of hair is found
on general body surface
portion of hair that we see from surface
hair shaft
a tube where hair develops
hair follicle
portion of hair that anchors hair into skin
hair root
sensory nerves surrounding base of each hair follicle
root hair plexus
bundle of smooth muscle which is connected to hair follicle
arrector pili muscle
fx. contracts with cold, fear, and rage
arrector pili muscle
why do old people bruise easily
don’t have hypodermis layer and have thin skin
another name for bruising
contusion
how is hair produced
begins at base of hair follicle
mitosis occurs producing cells that are gradually pushed toward the surface and hair grows longer
as cells move away from base, they die and keratinization is complete by the time hair reaches surface
what happens during the hair growth cycle
hair grows and sheds
hair on scalp grows for 2-5 years at rate of .33mm/day
what happens at the end of the hair growth cycle
follicle becomes inactive and hair is loose
2 types of hair
vellus hair
terminal hair
heavy and more deeply pigmented
terminal hair
peach fuzz located over much of body surface
vellus hair
where is terminal hair located
hair on head, eyebrows, eyelashes
where is vellus hair located
armpits, pubic area, and limbs UNTIL PUBERTY (then becomes terminal hairs)
what causes different hair colors
differences in structure and variations in pigment produced by melanocytes at hairs base (different forms of melanin)
how is hair color determined
genetically
how does chemical hair coloring work
disrupt hair cuticle and permit dyes to enter and stain inside of hair
discharge an oily lipid secretion (sebum) into hair follicles
sebaceous (oil) glands
fx. inhibits bacterial growth
lubricates and protects keratin of hair shaft
conditions surrounding skin
gland activity increases at puberty in response to increase levels of sex hormones
sebaceous glands
location of sebaceous gland
hair follicles
another name for sebaceous gland
oil gland
another name for sweat gland
sudoriferous gland
2 types of sweat glands
apocrine sweat glands
merocrine sweat glands
in armpits, around nipples, and in pubic region
apocrine sweat glands
coiled, tubular glands
merocrine sweat glands
secrete a thick sweat into hair follicles
apocrine sweat glands
discharge their secretions directly onto surface of skin
merocrine sweat glands
begin to fx at puberty
apocrine glands
much more numerous and widely distributed
merocrine glands
main fx. cool surface of skin via evaporation of sweat
merocrine glands
product is potentially odorous esp when bacteria feed on sweat
apocrine gland
visible portion
nail body
epidermis covered by nail body
nail bed
nail production occurs here
nail root
as basale cell activity decreases
epidermis thins
connections between epidermis and dermis weakens
more prone to injury, skin tears, and infections
decrease in calcium and phosphorus absorption
decrease in bone strength and density
melanocyte activity decreases
skin pales and more likely to get sunburned
oil gland activity decreased
skin becomes dry and scaly
sweat gland activity decrease
cannot lose heat well; easily overheat
blood supply in dermis decrease
skin becomes cool and person feels cold
thin gray/white hair
hair follicles stop functioning
dermis and hypodermis thins and elastic fibers
skin is weaker, less resilient, sags, and wrinkles
fx. support storage of minerals and lipids blood cell production protection leverage
fx of skeletal system
6 bone shapes
long bones flat bones irregular bones short bones sutural bones sesamoid bones
fingers
long bones
rips, scapulae
flat bones
vertebrae, facial
irregular bones
tarsals, carpals
short bones
small irregularly shaped bones between flat bones of the skull
sutural bones
develop inside tendons and are most commonly located near joints at knees, hands, and feet
sesamoid bones
only sesamoid bone everyone has
patella
what is the function of bumps in bones
places for attachments of muscles, tendons, and ligaments
what is the function of holes in bones
passageways for blood vessels and nerves
compact bone
diaphysis
primarily spongy bone
epiphysis
hollow tube within dialysis filled with yellow bone marrow
medullary cavity
2 major components of bone matrix
calcium phosphate and collagen fibers
makes up 2/3 weight of bone
calcium phosphate
very hard relatively inflexible and brittle
calcium phosphate
1/3 weight of bone
collagen fibers
strong, flexible and tough; can easily tolerate twisting and bending
collagen fibers
can withstand compression but likely to shatter when bent twisted or sudden impacts
calcium phosphate
what is the interactions of the 2 matrix of bone
allow bone to be strong and somewhat flexible and highly resistant to shattering
4 cells that are in bones
osteocytes
osteoblasts
osteogenic cells
osteclasts
mature bone cells that account for most cell production ; have cytoplasmic extensions that reach through canaliculi
osteocytes
fx. maintain protein and mineral context of matrix
participate in repair of damaged bone
osteocytes
produce new bone matrix by making and releasing proteins and other organic components of matrix; build bone
osteoblasts
these divide to make daughter cells that differentiate into osteoblasts
osteogenic cells
secrete acids and enzymes to dissolve bone matrix and release the stored minerals
osteoclasts
what is osteocytes relationship with lacunae
each osteocyte occupies a lacunae
what is osteocytes relationship with canaliculi
neighboring osteocytes are linked to each other through canaliculi to exchange nutrients, ions and small molecules with each other
in wall of diaphysis and is solid and strong
compact bone
matrix forms struts and plates called trabaculae; red bone marrow found between trabaculae
spongy bone
decrease weight of skeleton
allows stresses applied from many directions
supports and protects cells of red bone marrow
fx of spongy bone
structures in compact bone
osteon
central canal
perforating canal
basic functional unit and are cemented together; run parallel to long axis of shaft (more force applied to ends)
osteon
center of osteon and has blood vessels
central canal
run perpendicular to length of bone and has blood vessels; interconnect osteons, medullary cavity, and bones surface
perforating canal
2 types of bone marrow
yellow and red
in epiphysis of long bones and interior of sternum and ileum
red bone marrow
in medullary cavity and in some spongy bone; with age this replaces red marrow and it can be converted back to red if needed
yellow bone marrow
covers superficial layer of compact bone and is interwoven w tendons that are attached to bone; fibrous outer layer and cellular inner layer
periosteum
cellular layer that lines medullary cavity; layer of osteogenic cells
endosteum
process of bone formation
ossification
what type of tissue do most bones begin as
hyaline cartilage
what is the function of appositional growth
type of growth allows for bone diameter to increase
main blood vessels that serve our bones
nutrient artery and vein
how does the main blood vessels enter the bone
through a nutrient foramina is the diaphysis and then branches
process of continuously recycling and renewing the organic and mineral components of the bone matrix
remodeling
2 parts of bone remodeling
older mineral deposits are removed from bone and released into the circulation
circulating minerals are absorbed and deposited into bone
what is the function of osteoblasts and osteoclasts in bone remodeling
as quickly as osteoblasts form one osteon, osteoclasts remove another
with exercise
bones become thicker and stronger
without exercise
bones become thin and brittle
4 major hormones in bone development
calcitrol
growth hormone
thyroxine
sex hormones
from kidneys; needed for normal Ca and P absorption in digestive tract
calcitrol
from pituitary gland; stimulates reproduction of cartilage cells in epiphyseal cartilage
growth hormone
from thyroid gland; increase rate of osteoblast activity
thyroxine
from testes and ovaries; stimulates osteoblasts to produce bone faster than the rate at which epiphyseal cartilage explains
sex hormones
5 major vitamins and minerals that affect bone development
vit D
Ca and P
vit C
vit A
proper absorption of Ca and P
vit D
REQUIRED FOR COLLAGEN SYNTHESIS
vit c
stimulates osteoblast activity esp in children
vit A
importance of calcium ions in the body
99% is in skeleton and most abundant mineral in the body
the significance of bones to maintain calcium ion homeostasis
vital role in nerve impulses, muscle contractions, and blood clotting
2 hormones that maintain calcium ion homeostasis
parathyroid hormone (from parathyroid gland) parathyroid gland (from thyroid gland)
3 target sites and their fx
bones (storage)
digestive tract (absorption)
kidneys (excretion)
crack or break in a bone
fractures
how does a fracture heal
external callus; osteoclasts and blasts remodel the region from 4 mo-a year; when heal the callus is gone
fracture is internal; no break in skin
closed
fracture projects through skin; may lead to infection or uncontrolled bleeding
open
bone shatters
comminuted
only 1 side of shaft is broken and the other side is bent; occurs more in kids
green stick
break of a bone across its long axis
transverse
produce new and abnormal bone arrangements
displaced
break at the epiphyseal cartilage
epiphyseal
usually a very small sliver or crack in the bone
stress
how many bones do we have
206
has 80 bones
axial
has 126 bones
appendicular
skull 22 hyoid 1 auditory ossicles 6 vertebral column 26 thoracic cage 25
axial skeleton
pectoral girdle 4
pelvic girdle 2
upper limbs 60
lower limbs 60
appendicular skeleton
swirling throws particles against the sticky mucus on the walls of the nasal cavity
slows air movement to increase time for warming, humidification and dust removal
directs air toward olfactory receptors at the top of cavity
fx of nasal conchae
4 sets of paranasal sinuses
frontal
sphenoidal
ethmoidal
maxillary
fx. lighten the skull
provide extensive area of mucous epith
paranasal sinuses
fibrous areas between cranial bones and infantile skull
fontaneles
fx/ allow distortion of skull so it can pass through birth canal without damage
fontaneles
3 regions of the vertebrae
cervical 7
thoracic 12
lumbar 5
why do the vertebral bodies get larger as you move down the column
they enlarge since there is more for them to support
actually 5 fused vertebrae
sacrum
actually 3-5 fused vertebrae
coccyx
ribs
12 pairs
3 regions of the ribs
first 7- true ribs
next 3- false ribs
last 2- floating ribs
connected to sternum directly
true ribs
connected to sternum indirectly via merged costal cartilages
false ribs
not connected to sternum
floating ribs
another name for articulation
joints
where 2 bones interconnect
articulation
by amount of movement possible and type of tissue that binds bones together
fx of joints
3 types of joints
synarthrosis
amphiarthrosis
diarthrosis
immovable
synarthrosis
slightly movable
amphiarthrosis
freely movable
diarthrosis
very strong joints; movement between bones must be prevented (bones are close)
synarthrosis
two types of synarthrosis
fibrous and cartilaginous
dense connective tissue connects
fibrous in synarthrosis and amphiarthrosis
between bones of skull
suture
teeth in jaw
gomphosis
hyaline cart connects
cartilaginous of syn
fibrocartilage pad connects
cartilaginous of amp
ex of cartil in synarthrosis
synchondrosis - long bones and ribs to sternum
ex of fibrous amp
syndesmosis- distal end of tibia and fibula
ex of cart in amp
symphysis- between vertebra and symphysis pubis
synovial joints
diarthrosis
3 basic components of every synovial joint
articular cartilage
joint capsule
synovial membrane
hyaline cartilage covering of bone ends; decreases friction
articular cartilage
holds bone together
joint capsule
within joint cavity and within bursae
synovial fluid
lubrication
nutrient distribution
shock absorption
synovial fluid
small closed synovial fluid filled sacs located where a tendon or a ligament rubs against other tissues
bursa
tough, strong connective tissue structures that connect bones to bones
ligaments
fibrocartilage pad between bones within a synovial joint
meniscus
localized masses of fat to protect articular cartilage and act as packing material for the joint
fat pads
