BIOS 255 Week 3: Blood and Cardiovascular System Study Guide 2026
Chamberlain College
1. Which component of blood is responsible for maintaining osmotic pressure?
A. Albumin
B. Globulins
C. Fibrinogen
D. Hemoglobin
Answer: A
Rationale: Albumin is the most abundant plasma protein and is primarily responsible for
maintaining the blood’s colloid osmotic pressure.
2. What is the normal pH range of human blood?
A. 7.00 - 7.20
B. 7.25 - 7.35
C. 7.45 - 7.55
D. 7.35 - 7.45
Answer: D
Rationale: Human blood is slightly alkaline, with a narrow physiological range between
7.35 and 7.45.
,3. Which hormone, produced by the kidneys, stimulates the production of red
blood cells?
A. Calcitonin
B. Thrombopoietin
C. Insulin
D. Erythropoietin
Answer: D
Rationale: Erythropoietin (EPO) is released by the kidneys in response to low oxygen
levels to stimulate erythropoiesis in the bone marrow.
4. A hematocrit of 45% means that:
A. 45% of the blood volume is plasma
B. 45% of the blood volume is white blood cells
C. 45% of the blood volume is formed elements, mainly RBCs
D. The hemoglobin concentration is 45 g/dL
Answer: C
Rationale: Hematocrit represents the percentage of total blood volume occupied by
erythrocytes.
5. What is the average lifespan of a mature red blood cell?
A. 10 to 20 days
B. 6 months
C. 120 days
D. 1 year
Answer: C
Rationale: RBCs typically circulate for about 120 days before being trapped and destroyed
in the spleen or liver.
, 6. Which white blood cell is typically the first to arrive at a site of infection?
A. Lymphocyte
B. Neutrophil
C. Eosinophil
D. Monocyte
Answer: B
Rationale: Neutrophils are the most numerous leukocytes and act as the primary ‘first
responders’ to bacterial infection.
7. Heme is broken down into a yellow pigment called:
A. Stercobilin
B. Bilirubin
C. Transferrin
D. Ferritin
Answer: B
Rationale: During RBC recycling, the iron-free portion of heme is converted into bilirubin,
which is then processed by the liver.
8. Which cell type gives rise to all formed elements of the blood?
A. Hemocytoblast
B. Reticulocyte
C. Megakaryocyte
D. Lymphoblast
Answer: A
Rationale: Hemocytoblasts (pluripotent hematopoietic stem cells) are the precursor cells
for all blood cells.
Chamberlain College
1. Which component of blood is responsible for maintaining osmotic pressure?
A. Albumin
B. Globulins
C. Fibrinogen
D. Hemoglobin
Answer: A
Rationale: Albumin is the most abundant plasma protein and is primarily responsible for
maintaining the blood’s colloid osmotic pressure.
2. What is the normal pH range of human blood?
A. 7.00 - 7.20
B. 7.25 - 7.35
C. 7.45 - 7.55
D. 7.35 - 7.45
Answer: D
Rationale: Human blood is slightly alkaline, with a narrow physiological range between
7.35 and 7.45.
,3. Which hormone, produced by the kidneys, stimulates the production of red
blood cells?
A. Calcitonin
B. Thrombopoietin
C. Insulin
D. Erythropoietin
Answer: D
Rationale: Erythropoietin (EPO) is released by the kidneys in response to low oxygen
levels to stimulate erythropoiesis in the bone marrow.
4. A hematocrit of 45% means that:
A. 45% of the blood volume is plasma
B. 45% of the blood volume is white blood cells
C. 45% of the blood volume is formed elements, mainly RBCs
D. The hemoglobin concentration is 45 g/dL
Answer: C
Rationale: Hematocrit represents the percentage of total blood volume occupied by
erythrocytes.
5. What is the average lifespan of a mature red blood cell?
A. 10 to 20 days
B. 6 months
C. 120 days
D. 1 year
Answer: C
Rationale: RBCs typically circulate for about 120 days before being trapped and destroyed
in the spleen or liver.
, 6. Which white blood cell is typically the first to arrive at a site of infection?
A. Lymphocyte
B. Neutrophil
C. Eosinophil
D. Monocyte
Answer: B
Rationale: Neutrophils are the most numerous leukocytes and act as the primary ‘first
responders’ to bacterial infection.
7. Heme is broken down into a yellow pigment called:
A. Stercobilin
B. Bilirubin
C. Transferrin
D. Ferritin
Answer: B
Rationale: During RBC recycling, the iron-free portion of heme is converted into bilirubin,
which is then processed by the liver.
8. Which cell type gives rise to all formed elements of the blood?
A. Hemocytoblast
B. Reticulocyte
C. Megakaryocyte
D. Lymphoblast
Answer: A
Rationale: Hemocytoblasts (pluripotent hematopoietic stem cells) are the precursor cells
for all blood cells.
