AP&P Test 2 Flashcards
epithelial tissue
Becomes either a flat tissue or the lining of a cavity, avascular so no blood vessels (everything is tightly packed) Doesn’t bleed. Hooked up to the basement membrane.
Basement membrane
protein layer where epithelial and connective tissues join, thin layer of collagen and adhesive proteins
Connective tissue
widely spread cells, mainly consisting of fibers and ground substance. (Very abundant)
Functions of connective tissue
connecting organs, gives support and protection, storage of energy, heat protection, movement and transportation of materials.
8 types of epithelial tissues
Simple and stratified (squamous, cuboidal, and columnar) then Pseudostratified - oddly shaped but all the cells must touch basement membrane. Transitional - restricted to urinary system (bladder can stretch and contract)
3 types of connective tissue fibers
collagen, reticular, elastic.
fibroblasts
cells that make protein fibers and ground substance btwn the cells. A pure connective tissue cel
macrophages
move through connective tissue and phaygocytize foreign material/ activate immune system, arise from monocytes (WBC), monocytes become macrophages
neutrophilis
move through tissue looking for bacteria
plasma cells
come from lymphocytes (WBC) make antibodies to be delivered tot he blood stream.
mast cells
secrete histamine and herapin
histamine
dilates blood vessels so fluid can leak out which leads to swelling (pooling of blood/fluid)
herapin
prevents blood from clotting
adipocytes
(fat cells) store triglycerides for energy.
collagen fibers
large, tough resistant to stretch but still flexible. (Tendons - muscle to bone, Ligaments - bone to bone, and dermis)
reticular fibers
thin collagen fibers (mainly found in blood organs) they support the organs, keep them protected, give structural support (spleen = sack of blood that needs reticular fibers for support)
elastic fibers
thin and branching fibers made of elastin. stretch and recoil like a rubber band. Elastic = return to normal. Stretchy skin,lungs, arteries.
ground substance
gelatinous material where fiber and cells are suspended (glycoproteins and proteoglycans)
differentiation
tissue goes from unspecialized to specialized, stem cells becomes bone or cartilage or blood
metaplasia
tissue changes from 1 mature type to another, sometimes natrual and sometimes mutation. EX natural(girls vag goes from simple cuboidal to stratified squamous for their period and pregnancy) unnatural (mutation in cilia of smokers, change from pseudo-stratified to stratified squamous, could change back
hyperplasia
rapid growth through cell multiplication (EX women’s breasts swell during pregnancy from hormone production, womens uterus gets lost during period by hyperplasia is rapid growth so its ready for next period.
hypertrophy
enlargement of preexisting cells (EX gaining weight - adipose tissue swells to hold more fat, muscles swell to hold more contractile proteins)
atrophy
shrinkage from loss of cell size or #, due to lack of usage.
neoplasia
growth of a tumor/ abnormal tissue.
necrosis
pathological death of a tissue diseased or lacking function
apoptosis
programmed cell death
tight junctions
membranes are almost fused together through plasma membrane, a membrane protein, and intercellular space. Acts like a belt to keep cells tight to each other. Prevents things from passing in btwn cells, grooves match up in GI and urinary tracts
functions of tight junctions
things must pass through cell and be released by cell to move on, this gives cell control over what flows in and what flows out.
desmosomes
like a spot weld, snap on pants. Protects from mechanical stress. Prevents skin from coming off when you pinch it. Common in uterus, skin, heart. (gap btwn cells is spanned by mesh of filaments that are on protein plaque, cytoplasmic filaments also hook up w/ plaque)
gap junctions
communcating junctions, have a ring of 6 transmembrane proteins form a channel. Channel is for solutes to move from cell to cell and send electrical signals for communicating. Found in embryos, cardiac muscles, smooth muscles.
holocrine glands
ecretory cells disentigrate in order to deliver their product and some cell fragments [oil glands - scalp that gives us oil but also cell fragments on the scalp]
mucous membranes
contains epithelium, lamina propria, and muscularis mucosae. Lines passages to exterior, digestive, respiratory, urinary, reproductive. Mucous coating and cilia remove foreign things
lamina propria
loose connective tissue
muscularis mucousae
smooth muscel so membrane can change shape. Goblet cells screte mucin
synovial membranes
lines joints (only connective tissue), secretes synovial fluid w/ hyaluronic acid into joint. Fluid leaks out very easily.
serous membranes
internal membrane (simple squamous and lamina propria). Lines body cavities and internal organs. Secretes water to reduce friction of dynamic organs. Cancer can spread through serous cells.
exocrine glands
maintain connection to surface through ducts (epithelial tubes) EX sweat to skin, saliva to mouth, pancrease to small intestine. Variety of patterns. Connective tissue on the outside between lobes
ducts
travel through connective tissue.
acinus
cluster of enlarged simple cuboidal cells at the bulge of the duct, secreting forms here and then moves down the duct
endocrine glands
No ducts, secrete their products (hormones) directly into the blood stream.
hormones
any chemical that travels through the blood stream
serous secretion
thin, watery secretion (sweat, milk, tears, juices)
mucous secretion
produce mucin (glycoprotein) that absorbs water to become mucus
mixed glands
glands that are serous and mucus glands, ex: salivary glands
merocrine gland/secretion
product is released by exocytosis, store product in vesicle, exocytocized up and out of duct, only product gets secreted. gives us normal sweat, simple tubular gland, millions of them for colling us down.
aprocrine gland/secretion
intermediate secretion, some product, some cell, only in breast with milk. contains fatty acids, not activated until puberty. Mainly in armpit and groin, found near follicles and respond to stree and sex (body odor)
stroma
duct + connective tissue, capsule and extensions of capsule that separate the lobes.
parenchyma
cells that synthesize the secretion gland, produce secretion
4 types of epidermal cells
Langerhans, Merkel, Melanocytes, Keratinocytes
Langerhans
(dendretic) mainly found in the spinosum (maybe basale), can move around w/in the layer, modified macrophages. They come from monocytes (WBC’s) that come from bone marrow. Leaves marrow and enters the blood stream, w/in a day its in connective tissue and known as a macrophage. Macrophages are phaygocytic and help immune system to rid cells/tissues of foreign things. Some live whole life in spleen (break down blood), some in liver (““cells), some in lungs (““dust), brain (““dead cells). Some get into skin, once in skin known as Langerhans.
Merkel
(tactile) only found in stratum basale, sits on basement membrane. Has fingerlike projections, with nerve endings in them. Function: detecting pressure and touch in skin. high population of merkel cells in sensitive areas (penis, clit, nipple, tounge)
Melanocytes
Function: make a pgment called melanin (skin color) located in hair/brain
Keratinocytes
(stem cells in the basale): starts at layer 1 and moves up throughout the cell, standard epidermal cell, 30-40 days to get to the top.
5 layers of epidermis
All are stratum first: basale, spinsoum, granulosum, lucidum, corneum
stratum basale
its on basement membrane, very hydrophilic. Stem cells become keratinocytes. Melanocytes are located here.
stratum spinosum
thickest layer, tightly connected by desomsomes, capable of mitosis
stratum granulosome
appear to have granulues, 1 type of granule is keratinohyaline(make skin tough), another is lamellar(lipid that makes our skin water proof).
stratum lucidum
translucent layer of dead keratinocytes, dead skin filled with keratin.
stratum corneum
cells have lost all organelles (only keratin remains), flat against each other. Functions: protection, flake off when dead.
melanin distribution w/in cell
melanin is made in vesicles and carried up to be released in stratum spinosum (taken in through phaygocytosis) Lysosomes break down the melanin so at the top layer everyones skin is the same color (no melanin left). Spinosum put melainn on top of the nucleus as a “cap” to protect DNA inside of nucleus form UV rays. If you are albino then melaoncytes are not functioning properly (missing an enzyme)
dermis description
Connnective tissue layer wth collagen, reticular, and elastic fibers as well as ground substance, hair follicles, and sweat/oil glands.Fibroblasts responsible for making the fibers (most of the red comes from collagen). More vascular than the epidermis
dermal papillae
where dermis and epidermis connect, not a flat surface but perfectly jagged to increase surface area as well as joining dermis and epidermis to prevent shearing.
layers of the dermis
papillae and reticular
papillae
holds dermal papillae for connecting skin together, not very dense.
reticular
underneath papillae, mostly reticular fibers.
Sweat glands
filtrate into the plasma (500ml a day)
sebaceous glands
(oil glands) secrete sebum w/ broken down cell fragments. lanolin in skin cream is sheep sebum. Flask shaped gland w/ duct into hair follicle.
ceruminous gland
modified sweat glands in the external ear canal, secretion combines with sebum to produce ear wax (keeps ear drum flexible)
mammary glands
breasts of both sexes, lack of testosterone allows breasts to develop. Glandular tissue ony grows when woman is pregnant and lactating (no milk until pregnancy)
milk lines
2 rows of mammary glands running from thigh up to nipple
polythelia
additional rudimentary nipples.
Nails
clear, hard derivative of stratum corneum. Densely packed cells filled w/ hard keratin. Flat nails allo for sensitive fingerprints (back of finger leans against nail) Growth rate is 1 mm ina week. New cells are added via mitosis in nail matrix, nail plate is visible part of a nail.
lunule of nail
light crescent on bottom of nail face (not hard keratin yet)
eponchyium
(cuticle) ridge that protects the root.
hyponesium
where nail meets skin underneath
Hair
located in the stratum corneum and made of hard keratin, strong due to disulfide bridges btwn molecules, located everywhere
3 types of Hair
lanugo, vellus, terminal hair
lanugo
fine, unpigmented hair (fetal,kids)
vellus
fine, unpigmented hair (peach fuzz)
terminal hair
coarse, long, pigmented hair.
hair color
comes from melanin with the cortex of the hair
eumelanin
(brown and black) formed by MSH binding to a melaoncyte receptor
pheomelanin
(red and yellow) formed by agouti group binding to melanocyte receptor
Layers of the Hair
Cuticle - outside layer (epithelial sheath), Coretx - middle layer (location of melanin) Medulla - inner most layer
Structure of Hair(SOH): shaft
parts above the skin
SOH: root
parts within the follicle, below the skin
SOH: follicle
epidermal invagination of dermis, made up of epithelail cells and the tissue of the dermis starts to dive and continues untilt he follicle is formed.
SOH: bulb
swelling in the base where hair originates.
SOH: papillae
vascular tissue in bulb (capillaries get into papillae and supply blood for growth)
SOH: Epithelial root sheath
extension of epidermis
SOH: Connective root sheath
derived from the dermis
SOH: Hair receptors
have a nerve cell so they are sensitive to movement
SOH: Arrector pili
contracts to make hair stand up
Hair Growth
new hair starts growing when stem cells in bulge begin to divide and form a new epithelial root shealth (old hair is still in the follicle at this point). Cells in matrix begin to specialize into hair cells and bulb surround hair matrix. Cells become keratinzed and push up forcing new hairs out
4 stages of Hair Growth
Anagen - active growth (2-6 years) Catagen - transition phase (1-2 wekks) begins shriveling so the dermal papillae is inacive and no longer supplying the hair (bottom breaks off and is now a “club hair”)Telogen - resting phase (5-6 weeks) no longer a bulb, then back to Anagen
functions of Hair
too thin for warmth, sensory factors: alert us to crawling on skin, etc. Scalphair helps with heat retention. sexual and indivudal recognition. Beard and pubes indicate sexual maturity/ distriubte scent.
basal cell carcinoma
from cells of stratum basale, treated with removal/radiation
squamous cell carcinoma
arises from keratinocytes in stratum spinosum, if it metasizes into lymphnodes (lethal)
malignant melanoma
(most deadly cancer) arises from melanocytes of a preexisiting mole ABCDE - asymmetry, border irregularity, color mixed, diameter of 6mm, evloves over time
Wound Healing
cells along wall of cut release growth factors and try to seal it, blood is good because it cleans the cuts, blood vessel dilate due to histamine, plasma comes through w/ antibodies (cleaners) clotting factors and WBC’s. Macrophages and Leukocytes - clean up all the debris, (granulation tissue) cappilaries grow and fibroblasts deposit new collagen fibers (starts in 3-4 weeks and lasts up to 2 weeks).
Regeneration
replacement by mitosis, restores normal function (EX scab forms on skin, liver can regenerate
Fibrosis
replacement of damaged cells w/ scar tissue (collagen), helps hold organs together. Function is not restored to the tissue, seen in muslce injuries, lungs with TB, cuts and burns.
Keloid
healing of excessive fibrosis (raised scars)
1st degree Burn
affects only epidermis, most sunburns, typiclally no scars, maybe a blister.
2nd degree burn
epidermis and some of dermis but dermis is still intact, blisters, scars
3rd degree burn
completely destroys dermis, skin grafts needed, not as painful as a 2nd degree burn because nerves are destroyed.
interstitial growth of bone
groth form within (length) and it occurs in the metaphysis.
appositional growth of bone
growth from edge (width), about 10% of bone recycled per year.
medullary cavity
(marrow) space for bone marrow
diaphysis
shaft of the bone
epiphysis
end of the bone
endosteum
cellular lining on inside of medullary cavity.
periosteum
outside of the bone, it’s a cellular lining w/ connective tissue fibers. “Sharpey’s fibers” - hold the bone together.
articular cartilage
the joint surface where one bone meets another and is covered with hyaline cartilage
nutrient foramen
the hole where blood vessels enter the bone
perforating fibers
collagen fibers that penetrate into the bone matrix
osteogenic cells
(mitotic) stem cells that develop from embryonic mesenchymal cells. Found in the endosteum and inner layer of periosteum. Always multiply and some become osteobasts.
osteoblasts
bone forming, normally cuboidal, located underneath the endosteum and periosteum. NON mitotic, only formed by mitosis/differentiation of osteogenic cells. They produce osteoid = soft, unmineralized bone. Stimulated by stress//fractures on bones
osteocytes
former osteoblasts that got trapped in the bone matrix by minerals. They can be found lacunae which are connected by canaliculi for communication. Osteocytes are connected to each other by gap junctions to pass chemical information. Main function is to sense and react to stress.
osteoclasts
bone dissolving cells, develop from the same stem cells that give us blood as a pre-monocyte. Some get into blood stream and are called macrophages, others cluster and become osteclasts. Have a ruffled border that sits on the bone to increase surface area so bone resorption is more efficient. They reside in resportion bays - pits when bone is broken down
osteoid
soft, unmineralized bone made by the osteoblas
hydroxylapatite
a crystalized calcium phosphate salt that makes up about 85% of inorganic matter, 10% of inorganic matter is calcium carbonate.
organic matter
1/3 of weight of a bone, made up of proteoglycans and gylocoproteins.
canaliculi
chanels that connect lacunae.
lacunae
cavities that contain osteocytes.
osteon
basic structural unit of compact bone, made up of a central canal and lamallae.
concentric lamallae
layers of matrix concentrically arranged around a central (haversian) canal and connected by canaliculi.
volkmann’s canals
diagonal passages that join central canals
hyversian canals
(central) main canal that lamallae is formed around
bone regeneration
Osteoclasts dig tunnels down in to the bone through resorption bays, tunnels are then filled with osteogenic cells which become osteoblasts. Osteoblasts start creating new osteoid which is then mineralized and becomes hard bone, fills from the outside in which gives lamallae the oninon looking shapes. more holes in children because they are still growing so bones must conitually grow.
spongey bone
lattice structure of spicules and trabeculae. Trabeculae are thin plates. It is hard but since its less dense it has less weight. Its covered with endosteum and filled with bone marrow. The bone matrix is formed the same as that of compact bone but there are not as many osteons. No central canals becasue marrow is everywhere for nutrients, trabeculae grow along stress lines.
intramembranous ossification step 1
produces flat bones of the skull/manidble, 4 steps:1) mesenchyme condeneses into a soft sheet of tissue full of blood vessels( osteoprogenitor), mesenchymal cells line up on vessels and become osteoblasts and make osteoid.
intramembranous ossification step 2
calcium phosphate and otehr minerals crystalize on collagen fibers to harden the bone matrix. Osteoblasts become trapped and become osteocytes. More mesenchyme forms the periosteum to form trabeculae.Osteoblasts deposit bone and fill in spaces of trabeculae to creat compact bone on the outsides, this gives us the flat cranial bone with spongey bone inbetween.
Endochondral Ossification
development of long bones, starts with cartilage from mesenchyme, takes shape of bone. Osteoblasts mainly at epiphysis, build bone on top and bottom.
hypertrophy
cells are about to die, blood vessels get into cartilage and make osteoblasts to form new bone.
metaphysis
transitional region from cartilage to bone at each end of primary marrow.Epiphyseal plate - a thin wall of cartilage seperating primary and secondary marrow cavities, where growth occurs.
creation of hyversian system
certain ions are removed from blood plasma and deposited in bone tissue. Osteogenic cells create osteoblasts through mitosis, then they make osteoid (unmineralized bone) The osteoblast creat collagen fibers that spiral along the osteon in alternating directions. Fibers bceome incrusted w/ mineral, ion conc. must reach solubility product, crystals form hydroapatite - calcium and phosphate due to positive feedback loop
ectopic ossification
abnormal ossification (patella on puropose and good result, eyes, brains, arteris not good result)
remodeling a bone
osteoclasts dissolve bone so minerals can be released into the blood, this occurs at the ruffled border of the osteoclasts. Then they release H ions and attract Cl ions to form HCl which dissolves hydroxylapatite. The enzymes break down the collagen and the HCl (acid) breaks dwon the minerals. the tunneling of osteoclasts forms the Hyversian canals. Acid phosphtae and cathapin K are respobinble for breaking down the collagen.
reason for remodeling a bone
release minerals that we need and phosphates that we need. (DNA, RNA, ATP, phospholipids) Calcium is important to muscle contraction and nerve(neuron) function
hypocalcemia
defenciey of blood calcium, excessive nerve excitablity and muscle contractions, sodium channels are tough to open.
hypercalcemia
excess of blood calcium, too much at cell surface makes sodium channels less likely to open, depresses nervous system.
calcitriol
comes from within a chemical in our blood (7 dehydrocholesterol) that when hti by UV rays creats Vitamin D3. liver converts the vitamin D into calcitriol.
function of calcitriol
facillitate calcium and triate across our stomach, could become Rickets or Osteomlacia (soft bones)
calcitonin
secreted by calcium cells of thyroid gland when calcium conc. rises too high
functions of calcitonin
reduces osteoclasts activity quickly and increase calcium loss by kidneys. (regulates cells that break down bone, more so in kids)
parathyroid hormone
secreted by parathyroid gland, goal is to raise blood calcium levels.
function of parathyroid hormone
timulate enzyme in kidneys for last step of calcitriol synthesis.
osteoporosis
most common bone disease, bones become less dense and brittle due to loss of matrix and minerals. Biggest risk for post menopausal women, also old age.
treatments for osteoporosis
Hormone Replacement therapy which slows down breaking down of bones. Best treatment is prevention. Exercise and take in 1000mg of calcium a day, specially btwn ages 25-40. Some possible drugs that could help are: fosamax, boniva, reclast - slow osteoclasts down; evista - stimulates estrogen activity.
achondroplastic dwarfism
limbs stop growing eearly but head and torso remain some what normal, due to a genetic mutation.
pituitary dwarfism
could come from an injury or mutation, body is proportional just small.
pituitary gigantism
too much growth hormone is produced, adenoma
adenoma
cancerous growth of the pituitary gland
three primary germ layers
ectoderm, endoderm, and mesoderm
ectoderm
(outer) forms epidermis and nervous system
endoderm
(inner) form mucus membrane linings in GI and urinary tracts, as well as digestive glands
mesoderm
(middle) forms mesenchyme that grow into connective tissues.
Hyperdermis
(subcutaneous) has more adipose than dermal tissue. Functions include energy reservoir, thermal insulation. Hyperdermal injections are delivered here because of all of the blood vessels.
skin color
hemoglobin, carotene, and melanin
hemoglobin
red pigment of blood cells, visible through dermal collagen fibers
carotene
yellow pigment from veggies, fruits, egg yolks, mainly held in stratum corneum/subcutaneous fat
Melanin
produced by melanocytes, synthesis from UV radiation, gives us yellow, red, black, and brown. we all have same amount of melanocytes but skin color depends of what color melanin and how quickly it makes it.
cyanosis
lack of oxygen in blood (skin looks blue)
erythema
increased blood flow (skin looks red)
Jaundice
high levels of bilirubin which comes from breaking down blood cells. Seen in new borns because their liver isn’t fully formed and can’t keep up.
pallor
decreased blood flow (pale skin)
albinism
genetic variation, lack of melanin production
hematoma
bruise (bus, green, and purple coloring)
stretch marks
tearing of the fibers (connective tissue doesn’t heal in the same direction)
freckles and moles
cluster of melanocytes
hemangioma
(true birthmark) excessive amnt of capillaries right under dermis.
strawberry birthmarks
disappear after birth
cavernous birthmarks
disappear after a few years
port wine stains
stay for life
Functions of the Skin
barrier to water/UV. vitamin D synthesis(UV stimulates a cholesterol in our blood) Absorption (lack in Vitamin A and E for skin creams [sebum] take in 1-2% of oxygen. Sensory functions: temp, touch, pressure, vibration, pain. thermoregulation (sweat or shiver), and social functions
bone matrix
1/3 weight is organic tissue (collagen, GAG’s proteoglycans, glycoproteins) - these resist tension. 2/3 is minerals (85% hydroxyapatite, 15% calcium carbonate) - these resist compression.
erythropoetic
blood forming
Bone growth during puberty
more osteogenic activity, more chondrocytes at epiphyseal plate. Testosterone and estrogen stimulate osteoblasts activity. Steroids - close epiphyseal plate.
