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Flashcards in Erythrocyte Physiology - Pierce Deck (20):
1

What is the equation for hematocrit? 3

Height of RBCs / Total Height

2

What are the formed elements found in the blood? 6

Erythrocytes
Leukocytes
Platelets

3

Where does erythropoietic begin? 11

Begins in erythroblastic islands in the bone marrow

4

What is the precursor to erythrocytes? 11

Reticulocytes that mature upon entry into the circulation

5

What is the role of Erythropoietin? 12

Principle regulator of erythropoiesis

6

What is the role of HIF? 12

Hypoxia inducible factor

In hypoxic environments HIF is released which activates erythropoietin gene to produce erythropoietin which activates erythropoiesis

7

What cofactors are required for a normoblast to mature into a reticulocyte? 16

B12

Folate (B9)

8

Differentiate B12 Deficiency (and folate) from poor B12 absorption? 19

B12 & Folate deficiency --> megaloblastic macrocytic anemia

Poor B12 absorption --> pernicious anemia

9

What condition do we associate with iron deficiency? 20

Microcytic anemia

10

Differentiate non-heme iron vs heme iron 20

Heme iron is much more absorbent to the body

11

What enhances iron absorption? 21

Ascorbate (vitamin C)

12

What challenge does nonheme iron have to overcome that heme iron doesn't? 21

Nonheme iron (Fe3+) has to convert to Fe2+ before entry into the duodenum/upper jejunum

13

How does iron circulate in the blood? 21

As transferrin

14

What is the normal Hb for females and males> 23

14.0 g/dL - females
15.5 g/dL - males

15

Each gram of hemoglobin combines with how many mL of oxygen? 26

1.34 mL of oxygen per gram of hemoglobin

16

What does a left shift of the oxygen curve indicate? 28

Implies greater affinity of the blood for oxygen

17

What pathologies are associated with a right shift of the oxygen curve? 29

Anemia

18

What pathologies are associated with a left shift of the oxygen curve? 28

Polycythemia

19

Define anemia 40

Reduction of the total circulating red cell mass below normal limits

20

What is methemoglobinemia? What kind of shift would you expect? 43

Leftshift pathology

Increased met-hemoglobin (Fe3+ ferric)

Decreased oxygen availability so lets make more RBCs