3.1 ERYTHROKINETICS

Question 1

Dynamics of RBC production and destruction

Answer 1

ERYTHROKINETICS

Question 2

Collection of all stages of RBC throughout the body in the BM, PB, vascular spaces within
organs

Answer 2

Erythron

Question 3

refers only to the cells in circulation

Answer 3

RBC mass

Question 4

STIMULUS TO RED BLOOD CELL PRODUCTION

Answer 4

HYPOXIA

Question 5

Primary oxygen-sensing system LOC

Answer 5

Peritubular fibroblast of the kidney

Question 6

Ability to sense whether there is adequate O2 supply to the tissues; once inadequacy of
O2 supply is detected, they influence/trigger EPO production

Answer 6

Primary oxygen-sensing system

Question 7

First human hematopoietic growth factor to be identified

Answer 7

Erythropoietin

Question 8

Gene for EPO is located at

Answer 8

chromosome 7

Question 9

EPO Mediated by

Answer 9

GATA1

Question 10

primary source of EPO

Answer 10

Kidneys (peritubular interstitial cells)

Question 11

also secretes EPO (10%-15%) | primary source of EPO in the unborn

Answer 11

Liver

Question 12

Thermostable, nondialyzable, glycoprotein hormone that has carbohydrate unit & terminal
sialic acid unit

Answer 12

EPO Structure

Question 13

EPO MW

Answer 13

34 kD

Question 14

Promotes early release of reticulocytes from the BM

Answer 14

SHIFT/ STRESS RETICS

Question 15

major way in which EPO increases RBC mass

Answer 15

Prevents apoptotic cell death

Question 16

ERYTHROCYTE DESTRUCTION

Answer 16

ERYPTOSIS

Question 17

process of cellular aging

Answer 17

Senescence

Question 18

Changes that occur as the RBC ages

Answer 18

Alteration in the membrane
↓ ATP levels
↑ calcium
Appearance of senescent antigen
↓ pH

Question 19

Alteration in the membrane is caused by

Answer 19

loss of sialic acid and lipids

Question 20

↓ ATP levels due to loss of

Answer 20

glycolytic enzymes

Question 21

This makes RBCs more susceptible to destruction

Answer 21

Appearance of senescent antigen

Question 22

This promotes iron oxidation

Answer 22

↓ pH

Question 23

Extravascular Hemolysis

Answer 23

Macrophage-Mediated Hemolysis

Question 24

Fragmentation or Intravascular Hemolysis

Answer 24

Mechanical Hemolysis

Question 25

RBC destruction outside blood vessel by splenic macrophage

Answer 25

Macrophage-Mediated Hemolysis

Question 26

90% of aged red cell destruction

Answer 26

Macrophage-Mediated Hemolysis

Question 27

1. ↑ total bilirubin and indirect
   (unconjugated) bilirubin
2. Slightly ↑ lactate dehydrogenase activity
3. Sightly ↓ haptoglobin and hemopexin
4. Slightly ↑ free hemoglobin

Answer 27

Serum samples of Macrophage-Mediated Hemolysis

Question 28

1. ↑ total bilirubin and indirect
   (unconjugated) bilirubin
2. ↑ lactate dehydrogenase activity
3. ↓ haptoglobin and hemopexin
4. ↑ free hemoglobin

Answer 28

Serum of Mechanical Hemolysis

Question 29

1. ↑ urobilinogen
2. Free hemoglobin: Negative
3. Methemoglobin: Negative

Answer 29

Urine sample of Macrophage-Mediated Hemolysis

Question 30

1. ↑ urobilinogen
2. Free hemoglobin: Positive
3. Methemoglobin: Positive

Answer 30

Urine sample of Mechanical Hemolysis

Question 31

• Spherocytes are often present

Answer 31

Macrophage-Mediated Hemolysis

Question 32

Associated with Rh incompatibility

Answer 32

Macrophage-Mediated Hemolysis

Question 33

RBC rupture within the blood vessel

Answer 33

Mechanical Hemolysis

Question 34

10% of aged red cell destruction

Answer 34

Mechanical Hemolysis

Question 35

Schistocytes are often present

Answer 35

Mechanical Hemolysis

Question 36

Associated with ABO incompatibility

Answer 36

Mechanical Hemolysis

Question 37

In intravascular hemolysis, the rupture of RBCs results in the release of RBC contents (particularly hemoglobin) which leads to the presence of

Answer 37

free plasma hemoglobin.

Question 38

Three ways to salvage free plasma hemoglobin:

Answer 38

binding of haptoglobin to free plasma
hemoglobin

binding of hemopexin to metheme

metheme binds to albumin (temporarily)

Question 39

Heme portion of methemoglobin is called

Answer 39

metheme/hemin