Deck 8: Erythrocyte Production and Destruction

Question 1

Which of the following is true of red cell precursors as they mature?

A)The nuclear-to-cytoplasmic ratio increases.
B)The cells become larger.
C)The cytoplasm becomes less basophilic.
D)The nucleoli become more prominent.

Answer 1

The cytoplasm becomes less basophilic.

Question 2

What is the main site for iron storage in the bone marrow?

A)stem cells
B)transferrin molecules
C)endothelial cells
D)macrophages

Answer 2

macrophages

Question 3

Erythropoietin increases the number of red cells by all of the following mechanisms except

A)prolonging cell life span.
B)shortening cell division times.
C)allowing earlier cell egress from the bone marrow.
D)increasing the rate of hemoglobin synthesis.

Answer 3

prolonging cell life span.

Question 4

What mechanism is responsible for the destruction of the majority of normal senescent erythrocytes?

A)intravascular hemolysis
B)rupture by complement
C)phagocytosis by peripheral neutrophils
D)phagocytosis by splenic macrophages

Question 5

Which of the following correctly describes a normal mature erythrocyte?

A)a 7- to 8-mm biconcave disc that lives 120 days
B)a 7- to 8-mm spheroid that lives 120 days
C)a 12- to 15-mm spheroid that lives 80 days
D)a 12- to 15-mm biconcave disc that lives 80 days

Question 6

Abnormal concentrations of cations inside erythrocytes cause

A)spherocytosis.
B)senescence.
C)prolongation of survival.
D)sickling.

Question 7

Where is erythropoietin synthesized?

A)bone marrow
B)kidney
C)lymph nodes
D)spleen

Question 8

Depletion of serum haptoglobin indicates

A)decreased erythropoiesis.
B)extravascular hemolysis.
C)intravascular hemolysis.
D)increased phagocytosis of macrophages.

Question 9

Which of the following has a pyknotic nucleus?

A)pronormoblast
B)basophilic normoblast
C)polychromatophilic normoblast
D)orthochromic normoblast

Question 10

Programmed cell death is called

A)necrosis.
B)apoptosis.
C)hemolysis.
D)phagocytosis.

Question 11

Why do men typically have higher erythrocyte counts than women?

A)They weigh more and have more blood vessels.
B)They do not lose as much blood each month.
C)Testosterone stimulates erythropoiesis.
D)They have more oxygen in their blood.

Question 12

When compared with mature erythrocytes,reticulocytes

A)are larger and bluer on Wright stain from remnant ribonucleic acid (RNA).
B)are larger and have more vacuoles on Wright stain from remnant deoxyribonucleic acid (DNA).
C)stain pinker with new methylene blue.
D)still have a nucleus.

Question 13

What stimulates production of erythropoietin?

A)decreased red cell number in the bone marrow
B)increased peripheral red cell number
C)decreased iron stores
D)decreased oxygen level in tissue

Question 14

The breakdown products of heme go through several biochemical degradations to form

A)bilirubin.
B)protoporphyrin.
C)amino acids.
D)haptoglobin.