unit 2 flashcards: blood

second class gaining momentum,,.

why is blood classified as connective tissue

arise from mesenchyme, made of cells+extracellular matrix

ave pH of blood? ave vol of blood?

ave pH: 7.4

ave vol blood: 5L

what are the percentages of plasma, erythrocytes, and leukocytes and platelets in the blood

plasma: 55%

erythrocytes: 45%

buffy coat - leukocytes & platelets: <1%

what are the fxns of blood

transportation - O₂ → cells, CO₂ → lungs, nutrients GI → cells, waste from cells → kidn, hormones

regulation - body temp, body pH, fluid balance

protection - wbc- disease, blood proteins - antibodies, prevents loss - blood clots

name plasma proteins (in order of abundance)

albumin, globulins, fibrinogens, regulatory proteins

albumin

most abundant at ~58%, prod by liver

acts as carrier to shuttle certain molecules thru circulation, such as bilirubin, hormones, metals, vitamins; important blood buffer (resists changes in pH) major blood protein contrib to plasma osmotic pressure (pressure that helps keep water in bloodstream)

globulins

alpha + beta-globulins primarily transport hydrophobic molecules and hormones, some metals, and ions (Cu)

gamma-globulins (immunoglobs/antibodies) involved in defense - prod by type of immune cells

fibrinogens

prod by liver, forms fibrin threads that form blood clot

regulatory proteins

includes enzymes + hormones

what is erythropoiesis and what triggers it?

it is erythrocyte (rbc) prod, takes 3-5 days

that is triggered by hormones (erythropoietin); depends on adequate supplies of Fe, folic acid, amono acids, certain B vits - B12 needed for complete maturation of RBC

what organ is in charge of monitoring blood and prod hormone? what organ does this hormone target?

kidneys monitor blood and produce blood-making hormone, erythropoietin (EPO)

erythropoietin targets the red bone marrow

patients w advanced kidney disease often have anemia. explain this connection

their kidneys don’t prod enough erythropoietin (EPO), leading to fewer rbc

what is a hematocrit? give normal vals

percentage of total erythrocyte volume in blood (“blood fraction”)

males: 47% +_ 5%

females: 42%

life span of erythrocytes? what happens when they age? what organ known as erythrocytes “graveyard”

life span 100-120 days

lose flexibility, become inc rigid + fragile, contained hemoglobin begins to degenerate

spleen bc small circ channels. try to squeeze them rupture

what is hemoglobin? how many O₂ can each Fe and each hemglob molecule carry?

transported by rbc, protein that makes them red

binds easily and reversibly w oxy, transports oxy and co2

each iron holds 1 O₂, each hemglob holds 4 Fe

what is hemoglobin made of?

heme: pigment, source of iron in body

globin: (responsib for structure) 4 polypeptide chains, mother cells in bone marrow, 2 α 2 β; any abnorms in chains can alter phys character of hemglob

when erythro destroyed, body processes three components of hemoglobin. list them

globin: amino acids, heme: iron + porphyrin → bilirubin

explain what ultimately happens to globin (non-protein)

breaks into amino acid, can be reused to prod other proteins

explain what ultimately happens to heme (protein) (Fe, organic lattice)

iron: removed and recycled in spleen

porphyrin: converted to bilirubin

what are norm vals of hemglob in humans?

14-20 g/100mL in infants

13-18 g/100mL in adult males

12-16 g/100mL in adult females

what determines whether blood is light or dull red? what do the colors mean?

oxyhemoglobin- oxy binds to iron

deoxyhemoglobin (reduced hemoglobin)- detaches from iron

can hemglob carry only oxy? explain

hemoglobin can carry O₂, CO₂

know blood types and what they mean in terms of what antibodies (agglutinins) and what agglutinogen (antigen) is present in erythrocytes

RBC A: Anti-B antibodies (agglutinins), A antigen (agglutinogen)

RBC B: anti-A antibodies, B antigen

RBC AB: no antibodies, A and B antigens

RBC O: anti-A and B antibodies, no antigens

RBC Rh (D): if Rh protein present, blood type +; if absent, Rh -

blood type donation

O can donate to anyone, can only receive O

A can donate to A and AB, but only receive A and O

B can donate to B and AB, but receive from B and O

AB can donate to AB, but can receive from anyone

pos Rh can donate to Rh+, can receive both Rh+ and -

neg Rh can donate to Rh+ and -, only receive Rh-

difference between antibodies and antigens

antigens are markers on the surface of the rbc that ID them to immune syst

antibodies are proteins prod by immune syst to recognize and attack foreign substances

which type of blood is the universal donor/recipient in the USA? (ABO and Rh)

universal donor: O-

universal recipient: AB+

which blood cells are the only ones considered cells and which ones are not? explain why

white blood cells are the only ones considered cells because they have a nucleus and usual organelles

classify leukocytes into granulocytes and agranulocytes and why they are classified as such

granulocytes: basophils, neutrophils, eosinophils - they have membrane-bound cytoplasmic granules

agranulocytes: lymphocytes, monocytes - they lack membrane-bound cytoplasmic granules

which white blood cells are the most common? least common?

most common: neutrophils (50-70%)

least common: basophils (0.5 - 1%)

granulocyte: desc neutrophils and their fxn

twice as large as rbc; stain pale lilac w v fine granules that are hard to see

granules lilac bc “neutro=neutral, phils=loving.” their granules take up both basic (blue) and acidic (red) dyes

nuclei consisting of 3-6 lobes; active in phagocytes (eat bacteria/dead cells); respond quickly to tissue destruction by bacteria or fungus; they are body’s bacterial slayers; numbers inc during acute bacterial infections

granules - lysoszyme: kill bacteria; oxidants such as hydrogen peroxide; defensins - poke holes

granulocyte: desc eosinophils and their fxn

usually found in tissues besides blood/bone marrow, place w most is GI

~ same size as neutrophils; deep red w 2 lobes, large granules stain red

lysosome-like but lacking enzymes specifically for digesting bacteria; parasitic worms - release enzymes from cytoplasmic granules onto parasite’s surface, digesting it away

granulocytes: desc basophils and their fxns

large histamine-containing granules; similar fxn to mast cells - bind to IgE (immunoglobulin), causes cells to release histamine. release of histamine intensifies inflammatory rxns

affinity for basic dyes so they stain purplish black (baso=basic); deep purple nucleus w U or S shape and 2/3 lobes

agranulocytes: desc lymphocytes and their fxns

small, round w large, round, dark nucleus

B Lymphocytes - attack bacteria, viruses, toxins; plasma cells→antibodies (Ig=immunoglobin); memory cells

T cells/lymphocytes - manage + direct immune response; some directly attack foreign cells + virus-infected cells

NKC - natural killer cells; attack abnorm + infected cells

recirculate - blood→interstitial space→lymphatic fluid→blood

agranulocytes: desc monocytes and their fxns

have abundant pale-blue cytoplasm + a darkly staining purple nucleus, which is distinctively U/kidney shaped; take longer to get there but arrive in larger nums; destroy more microbes; migrate from blood into tissues where they enlarge + become macrophages (phagocytic)

what molecules enhance the prod of leukocytes?

messengers

interleukins: numbered (eg IL-3, IL-5)

colony-stimulating factors (CSFs): named for the leukocyte pop they stim (granulocyte-CSF (G-CSF) stims prod of granulocytes)

what is leukocytosis and what is its significance?

it is a high white blood cell count: 11,000

usually a sign of the body’s immune system being activated, often due to infection or inflammation

what are platelets?

essential for clotting process that occurs in plasma when bvs rupture/their lining is injured; by sticking to damaged site, platelets form temp plug that helps seal break

since they are anucleate (w/o nucleus), age quickly and degen in ~10 days if not involved in clotting; in meantime, they circulate freely, keeping mobile but inactive

what cells give rise to platelets?

stem cells: megacaryoblasts

precursor cells: megacaryoblasts

platelets are cellular fragments of megakaryocytes

what is hemostasis? what are the steps and their order? what is needed to prod fibrin?

hemo=blood, stasis=halting = sequence of responses that stop bleeding

3 steps: (1) vascular spasms (bv constrict), (2) platelet plug formation, (3) coagulation, blood clotting

fibrinogen (plasma protein), thrombin

vascular spasms

serotonin → leads to blood vessel constriction (vasoconstrict vessel) → 20/30 mins - less blood loss during clotting

platelet plug formation

exposed collagen fibers, platelets attach → platelet activates → release granules content → serotonin (leads back to vasc spasm)

release granules content → ADP → adhesion (sticky) → temp platelet plug

coagulation (clotting)

extrinsic → tissue factor, outside the blood vessel, faster; intrinsic → all clotting factors are in blood, slower

→ prothrombin activator → prothrombin (inactive); → thrombin (inactive) → fibrinogen

thrombin → fibrin → permanent clot

compare and contrast extrinsic and intrinsic hemostatic pathways

extrinsic: tissue factor, outside the blood vessel, faster (external tissue damage)

intrinsic: all clotting factors are in blood, slower (internal tissue damage)

what is serum

when platelets contract, they pull on surrounding fibrin strands, squeezing serum, compacting the clot and drawing the ruptured edges of the bv closer together

(plasma w/o clotting factors)

what is clot retraction

when platelets contract, they pull on surrounding fibrin strands, squeezing serum, compacting the clot and drawing the ruptured edges of the bv closer together; as clot retraction occurring, vessel healing is taking place

what is plasmin? what does it do?

activated plasminogen; breaks down fibrin; body tissues + blood contain substances that activate plasminogen to plasmin