functions of blood

Question 1

when blood is centrifuged, what do we see

Answer 1

-plama layer, buffy coat (has plt, WBC), formed elements (rbc)

Question 2

what’s the difference between plasma and serum

Answer 2

-plasma contains fibrinogen so serum is plasma without fibrinogen and other clotting factors

Question 3

what’s the most abundant cation in the plasma and interstitial fluid? why are they not the same if they are both extracellular

Answer 3

• Na for both
• a bit less Na in the interstitial fluid because in the fluid, we have lots of proteins that are negatively charged that cause cations to bind to them

Question 4

what are the main anions in the plasma and interstitial fluid? what are the main anions in the intracellular fluids?

Answer 4

• Cl for both

- anions- HPO4

Question 5

what is anion gap

Answer 5

• unmeasured anions in the plasma usually the anions that are from negatively charged proteins
• equation: Na- (Cl+HCO3)
• useful in diagnosing metabolic acidosis

Question 6

what does hypoalbuninemia do to the anion gap?

Answer 6

-increases the gap

Question 7

what is the oncotic pressure

Answer 7

• the osmotic pressure

- the amount of solute or molality of the plasma that allows it to keep the solute in and draw fluid in as well

Question 8

colloid osmotic pressure

Answer 8

• osmotic pressure produced by the plasma proteins

Question 9

what’s the normal oncotic pressure

Answer 9

25 mmHg

Question 10

albumin

Answer 10

• makes up the most of plasma and is responsible for approx. 70-80% of colloid pressure
• also important for tx of freee fatty acids, ca, copper, steroids, bilirubin and drugs
• without it =edema

Question 11

transferrin

Answer 11

-free iron is toxic so it helps to tx iron to bone marrow to make RBC

Question 12

haptoglobin

Answer 12

-binds free hemoglobin that can enter the plasma after RBC lysis and this complex can’t be excreted by the kidney (too big) so it’s phagocytosed and the iron is conserved and recycled -done in liver

Question 13

*what would happen to plasma hgb and haptoglobin leels during an episode of increased intravascular hemolysis?

Answer 13

-haptoglobin would decrease b/c it would be binding to Hgb being released into the plama via lysis (so hgb would increase) but the half-life of that complex is only 90 min so we would see a lot of elimination of the haptoglobin vs when it’s not bound and has a half life of 5 days

Question 14

what is hematopoiesis and what are the steps

Answer 14

• the making of blood cells
• starts from a stem cell and turns into progenitor cells that become one of the cells that is in demand
• when progenitors first maturing, they have proliferative potential but as they mature they get more and more differentiated

Question 15

what kind of cells do lymphoid progenitor cells differentiate into? Myeloid progenitor cells?

Answer 15

lympohoid- t cells, b cells, nk cells =lymphocytes

myeloid- everything else- neutrophils, basophils, eosinophis, plt, RBC

Question 16

polycythemia

Answer 16

too many rbcs

Question 17

how many RBCs are made daily

Answer 17

200 billion

Question 18

what is the process of RBC synthesis

Answer 18

hemopoetic stem cell-> erythropoietin -> erythroblasts (decrease in nucleus)-> enter blood stream and enter as immature erythrocytines (reticulocytes) -> mature erythrocytes

Question 19

what indicates a recent increase in erythropoiesis?

Answer 19

increased reticulocytes b/c half life is only 24-48 hr

Question 20

what produces erythropoietin?

Answer 20

kidneys- does so when it senses decrease in oxygen

Question 21

how is erythropoietin made in the kidneys? is there anything that regulates this?

Answer 21

• it is made via binding of HIF alpha (hypoxia induced factor alpha) to HIF beta that causes an increase in translation of erythropoietin
• HIF alpha is constantly being made but with enough oxygen (thus no need for more erythropoietin), we have an enzyme that hydroxylates HIFalpha and stops it’s activity by making it bind to hippel landau protein

Question 22

when rbcs broken down, what is the porphyrin ring turned into

Answer 22

bilirubin

Question 23

plt

Answer 23

• nucleus free
• secrete factors and change shape for coagulation
• activated when glycoproteins on their surface bind collagen at site of injury

Question 24

what is the function of thrombopoitin

Answer 24

-stimulates megakaryocyte progenitor cells to begin making plt

Question 25

what makes thrombopoetin? how are plt made

Answer 25

• THE LIVER and BONE MARROW- (not kidneys like for erythropoietin)
• plt synth- megakaryocyte precursors under go ENDOMITOSIS (mitosis without splitting the cytoplasm so have a bunch of new ones in one megakaryocyte precursor)
• get a mature megakaryocyte that produces 100-1000 plt

Question 26

what stops plt synth

Answer 26

-plt bind to thrombopoesis and degrade it, stopping plt synth =negative feedback mech