Erythrocytes

Question 1

Life span

Answer 1

120 days

Question 2

Source of energy

Answer 2

• 90% used in glycolysis
• 10% used in HMP shunt

Question 3

Membrane contains ____, which allows RBCs to ____

Answer 3

• Cl−/HCO₃− antiporter
• Export HCO₃− and transport CO₂ from the periphery to the lungs for elimination

Question 4

____ color on ____ stain of reticulocytes represents residual ribosomal RNA

Answer 4

• Bluish
• Wright stain

Question 5

What feature of the erythrocyte structure permits easy gas exchange of oxygen and carbon dioxide?

Answer 5

The biconcave disc shape permits a high surface area to volume ratio and facilitates gas exchange

Question 6

What molecule do erythrocytes depend upon exclusively for energy?

Answer 6

Glucose; remember, they cannot use ketones for energy

Question 7

Where does an erythrocyte obtain the adenosine triphosphate that it needs for energy?

Answer 7

• Glucose
  
  • 90% is anaerobically degraded to lactate
  • 10% goes to the HMP shunt

Question 8

How do erythrocytes facilitate transport of carbon dioxide away from the peripheral tissues?

Answer 8

The chloride-bicarbonate antiport produces a physiologic chloride shift, resulting in cellular loss of chloride and gain of bicarbonate (and thus carbon dioxide)

Question 9

How would you describe a peripheral blood smear that shows an increased number of red blood cells and numerous immature red blood cells?

Answer 9

There is an erythrocytosis or polycythemia (increased number of cells) and a reticulocytosis (increased immature cells)

Question 10

How would you describe a peripheral blood smear showing red blood cells of varying sizes and of varying shapes?

Answer 10

This smear exhibits anisocytosis (varying sizes) and poikilocytosis (varying shapes)

Question 11

Sites of fetal erythropoiesis

Answer 11

• Yolk sac
  
  • 3–8 weeks
• Liver
  
  • 6 weeks–birth
• Spleen
  
  • 10–28 weeks
• Bone marrow
  
  • 18 weeks to adult
• Memory aid:*
• Young Liver Synthesizes Blood