A&P exam 3 Flashcards
how does lymph flow through the body
blood capillaries, interstitial space, lymphatic capillaries, vessels, trunk, duct, subclavian veins
what allows lymph to enter the lymph vessels
- inter-endothelial junctions: 1-way microvalves made of endothelium and smooth muscle
- permeability: not tightly joined, increases interstitial fluid to open valves
where are lymph capillaries located
everywhere except CNS, bone marrow, bones, teeth, cornea
when interstitial fluid pressure > capillary fluid pressure what happens
flap opens, lymph enters
when interstitial fluid pressure < capillary fluid pressure what happens
flap closes, doesn’t enter
do proteins enter lymph capillaries easily or hard
easily, but pathogens also enter easily
function of lymph nodes
cleanse lymph using macrophages to destroy microorganisms so they aren’t transferred through
where are lymph nodes activated
where dendritic cells bring back antigens to activate T cells
3 parts of lymph nodes
cortex: superficial, has dense cells
medulla: inner region w/ T and B cells
lymph sinuses: macrophages
what is found in germinal center
plasma cells and memory B cells
what is the largest lymph organ
spleen
what is mucosa associated lymphatic tissue
protects passages that are open to exterior; ex) tonsils
what makes up 1st line of defense
external membranes like skin and mucosa
lymphocytes
T and B cells that are main immune system warriors and protect against antigens
macrophages
activate T cells, phagocytize foreign substances
dendritic cells
capture, process, present antigens to T cells
reticular cells
produce fiber network that supports other cells in lymph tissue
is the immune system an organ system
no, it’s a functional system
what makes up 2nd defense
internal defenses that respond quickly
what are 2 parts of innate system
non-specific: 1st and 2nd line defense
what’s included in adaptive defense system
specific- 3rd line defense
does adaptive defense system have memory
yes, it does and we can build it
what’s included in innate defenses
skin, mucus, phagocytes, inflammation, fever, antimicrobial proteins, natural killer cells
what’s included in adaptive defenses
humoral immunity: B cells and cellular immunity: T cells
what are innate defense surface barriers
acid: inhibits bacterial growth
lysozymes: saliva, mucus, destroy bacteria
mucin: trap microorganisms
defensins: antimicrobial peptides
def natural killer cells
non-phagocytic defensive cells in blood and lymph that can kill cells before the adaptive immune system is activated
how do natural killer cells do their job
induce apoptosis on infected target cell, enhance inflammatory response
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benefit of inflammatory response
prevents spread of damaging agents, dispose cell debris, alert adaptive immune system, be ready for repair
what may be released as part of inflammatory response
cytokines, histamine, kinins, prostaglandis, leukotreines, plasma protein
2 types of phagocytes
macrophages: leave bloodstream in search of foreign substances
neutrophils: WBC becomes phagocytic after entering foreign substances
what do inflammatory chemicals do
dilate arterioles, increase capillary permeability, attract phagocytes
4 steps of phagocyte mobilization
leukocytosis: increase WBC
margination: phagocytes cling to inner wall
diapedesis: neutrophils flatten and squeeze through capillary walls
chemotaxis: draw neutrophils and WBC to injury site
what do antimicrobial proteins do
attack microorganisms directly to not allow for reproduction
what do larger vs smaller antimicrobial proteins do
larger: lytic enzymes to target cells
smaller: disrupt structure of cells
3 types of antimicrobial proteins
interferons, complement, transferrin iron-binding
what are interferons important for
interfere w/ viral replication of healthy cells, help fight cancer
what do alpha and beta interferons have
anti-viral properties, activate natural killer cells
what do gamma interferons do
enhance T cell activity, secreted by lymphocytes
3 types of effector proteins in complement system
classical, lectin, alternative
what does C3 turn into
opsonizes
what does C3a turn into
inflammatory response
which system are antibodies part of
adaptive
can innate immune system activate adaptive immune system
yes
what must third line defense be primed by
initial exposure
characteristics of 3rd line defense
antigen specific, systemic, memory
2 types of adaptive defense
humoral and cellular immunity
which cells attack target cells
direct lymphocytes
which lymphocytes are phagocytotic
indirect lymphocytes
what mediates humoral immunity
antibodies
what mediates cellular immunity
cells like lymphocytes
are incomplete antigens immunogenic
no, they are reactive but not immunogenic
are complete antigens reactive and immunogenic
yes they are both
do b lymphocytes have humoral response
yes
do t lymphocytes have cellular response
yes
do b lymphocytes secrete antibodies
yes
do t lymphocytes secrete antibodies
no
site of origin for b and t lymphocytes
red bone marrow
site of maturation for b lymphocytes
red bone marrow
site maturation for t lymphocytes
thymus
effector cells of b lymphocytes
plasma
effector cells of t lymphocytes
cytotoxic and regulatory
do b or t cells have memory formation
both cells do
what do antigen-presenting cells do
engulf antigens and send signals for t cells
class 1 vs class 2 MHC
what is made of the innate system
(1) skin, mucus, membrane secretions, (2) phagocytes, natural killer cells, antimicrobial proteins, fever, inflammatory response
what is made of the adaptive defense system
(3) humoral and cellular immunity of T and B lymphocytes
what are antigenic determinants
immunogenic part of the antigen
how many antigenic determinants can mobilize many lymphocytes
1 can mobilize many
what do memory cells do
mount response in the future, are long lived, more exposure leads to faster response
when do antibody levels peak for humoral memory cells
2-3 days after exposure
what activates t cells
antigen presenting cells that bind to MHC complex
cellular immunity primary response includes
helper cells: activate B cells
cytotoxic cells: directly attack/kill c ells
regulatory: dampen immune response
when does immune response peak for cellular immunity
1 week
are memory cells included in primary or secondary response of cellular immunity
secondary
regulatory t cells function
dampen immune response, prevent autoimmune reaction
memory cells function
respond to future attack
b cells function
part of humoral response, have antibodies, mature in red bone marrow
helper t cells function
cellular immunity, target intracellular pathogens, mature in thymus
do b lymphocytes attack intra or extracellular pathogens
extracellular
do t lymphocytes attack intra or extracellular pathogens
intracellular
where do b cells become immunocompetent
red bone marrow
where do lymphocytes soon to be t cells develop immunocompetence
thymus
where do lymphocytes go after leaving red bone marrow
spleen, etc where they mature
def checkpoint inhibitor
drugs that block checkpoint which allows immune system to attack cancer cell
what is immunotherapy used for
what does the complement system do
for both innate and adaptive it activates antibodies and lectins to prevent pathogens from pass ing through
what activates complement proteins
pathogens or pathogen-bound antibodies that kill bacteria and other cell types
where do t cells mature
thymus
what does medulla of lymph node contain
b and t cells
2 types of lymph tissue
diffuse: loose arrangement
lymphoid follicles: solid, tightly packed
what activates t cells
macrophages
what are the secondary lymph organs
peyer’s patch, appendix, lymph nodes, tonsils, spleen
where is MALT located
tonsils, peyer’s patch, appendix
where do lymphatic vessels transport lymph to
cardiovascular system
what’s the difference b/w lysozome and mucin
lysozomes use enzymes to destroy bacteria in lungs and tears, mucin trap microorganisms in respiratory tract, etc
what are defensins
part of 1st immune response, antimicrobial peptides that control bacterial growth
what are the first responders for innate response
phagocytes
is completent system naturally active or innactive
innactive at rest
3 types of phagocytes
macrophages, monocytes, neutrophils
what do natural killer cells release
cytokines and cytoplasmic granules
steps of phagocytosis
1) adherence of the pathogen/debris to phagocytic cell
2) pseudopods forms and wraps around the pathogen/debris
3) phagosome is formed by engulfed cell
4) phagosome and lysosome fuse forming phagolysosome
5) acidification/digestion of pathogen/debris in phagolysosome,
6) exocytosis
function of hypodermis
anchors skin to muscle,
is hypodermis a layer of the skin
not technically
4 cell types of epidermis
keratinocytes, melanocytes, dendritic cells, merkel cells
keratinocytes def
produce keratin, most abundant, from stratum basale, mitosis
how often does our epidermis regenerate completely
25-45 days due to regeneration of keratinocytes
melanocytes
produce melanin. in stratum basale, protects from UV
dendritic cells
phagocytes, immune system activator
merkel cells
sensory receptor for touch
what does thickness of epidermis layers depend on
exposure to friction
what cells make up stratum basale
10-25% melanocytes, continuously dividing
what is the prickly layer of skin made of mostly keratinoctes and dendritic cells
stratum spinosum
where does keratinization begin
stratum granuolsum
what is the water resistant layer of skin
stratum granulosum
does stratum granulosum have blood supply
no blood supply
what layer is only present in thick skin
stratum lucidum
what is the thickest and outermost layer
stratum corneum
what layer of skin do we shed regulatrly
stratum corneum
which skin layer has glycolipids
stratum granulosum
what type of tissue is papillary and why
loose, elastin, collagen to allow phagocytes to move freely, is superficial and enhances friction
reticular layer purpose
give supporting strength
what does hemoglobin do for skin
causes pinkish hue of fair skin
what does carotene do for skin
causes yellow/orange color
2 forms of melanin
brown/black or reddish yellow depending on where you live
BMR def
energy cost of living, essential activities
what factors influence BMR
age, gender, body temp, stress, thyroxine
what is thyroxine used for
metabolic hormone, determines BMR, uses ATP to operate Na/K pump, consumes oxygen and heat production
what is the metabolic hormone we need to know
thyroxine
what hormones indicate hunger
ghrelin, glucagon
what are neural signals mediated by
vagus nerve
total metabolic rate
includes BMR, thermal effect of food, and physical activity
*amount of heat produced by all chemical reactions and work
how much heat is lost insensible through evaporation
10%
how does the hypothalamus help with thermoregulation
receives info from central thermoreceptors (core) and peripheral thermoreceptors (skin)
what happens for infants to thermoregulate that’s different than adults
increase metabolic rate and thyroxine release
heat loss thermoregulation mechanisms
bv dilation, enhanced sweating
thermoregulation heat promoting mechanisms
shivering, increased metabolic rate, bv constriction
hyperthermia
BT above 105 F
heat stroke
neuro, physical, possible organ damage
hypothermia
BT below 70F, shivering stopped
compare humoral and cellular immunity
humoral= antibody cellular= cells attacking (lymphocytes)
MHC I vs MHC II location
I: endogenous= inside cell
II: exogenous= outside cell
how much of the stratum basale are melanocytes
10-25%
where does energy lost as heat go
making bonds, muscle contraction, friction from blood flow
what does leptin do
suppress appetite, suppress neuropeptide Y (enhances appetitie normally)
def thermoregulation
ability to regulate CORE temp
