BIOL 252 Human Anatomy & Physiology II w/Lab
| Module 1 Exam Review 70+ Questions and
Answers -Summary | LockDown Browser |
Portage Learning
## SECTION 1: BLOOD COMPOSITION AND PROPERTIES
**Q1. Which component makes up the largest percentage of plasma by weight?**
A) Electrolytes
B) Glucose
C) Proteins
D) Lipids
**Answer: C) Proteins**
**Rationale:** Plasma proteins (albumin, globulins, fibrinogen) constitute about 7-8% of plasma
by weight, making them the largest component by weight after water. They are essential for
osmotic pressure maintenance, transport, and immune function.
---
**Q2. The buffy coat in centrifuged blood contains:**
A) Erythrocytes only
B) Leukocytes and platelets
C) Plasma only
D) All formed elements
**Answer: B) Leukocytes and platelets**
,**Rationale:** When blood is centrifuged, the buffy coat is the thin, whitish layer that forms
between the packed erythrocytes (bottom) and plasma (top). It contains leukocytes (white blood
cells) and platelets (thrombocytes), comprising less than 1% of total blood volume.
---
**Q3. Which of the following is a nitrogenous waste product transported by blood?**
A) Glucose
B) Amino acids
C) Urea
D) Cholesterol
**Answer: C) Urea**
**Rationale:** Urea is a nitrogenous waste product formed in the liver from the breakdown of
amino acids (protein metabolism). Blood transports urea from the liver to the kidneys for
filtration and excretion in urine. Other nitrogenous wastes include uric acid and creatinine.
---
**Q4. Blood temperature is approximately:**
A) 35.0°C (95.0°F)
B) 38.0°C (100.4°F)
C) 37.0°C (98.6°F)
D) 39.5°C (103.1°F)
**Answer: B) 38.0°C (100.4°F)**
**Rationale:** Blood temperature is slightly higher than normal core body temperature,
averaging about 38°C (100.4°F). This is because blood circulation distributes heat generated by
metabolic processes throughout the body, helping to maintain thermal homeostasis.
,---
**Q5. The viscosity of blood is primarily due to:**
A) Plasma water content
B) Erythrocytes and plasma proteins
C) Leukocyte count
D) Electrolyte concentration
**Answer: B) Erythrocytes and plasma proteins**
**Rationale:** Blood viscosity depends mainly on the concentration of erythrocytes (RBCs) and
plasma proteins, especially albumin and fibrinogen. Normal blood viscosity is about 4-5 times
that of water. Increased viscosity (as in polycythemia) increases resistance to blood flow and
cardiac workload.
---
**Q6. Which stem cell gives rise to all formed elements of the blood?**
A) Lymphoid stem cell
B) Myeloid stem cell
C) Hemocytoblast
D) Megakaryocyte
**Answer: C) Hemocytoblast**
**Rationale:** The hemocytoblast is the multipotent hematopoietic stem cell residing in the red
bone marrow that differentiates into all types of blood cells, including erythrocytes, leukocytes,
and platelets.
---
**Q7. What is the average lifespan of a mature erythrocyte in the human body?**
, A) 30 days
B) 60 days
C) 90 days
D) 120 days
**Answer: D) 120 days**
**Rationale:** Due to the lack of a nucleus and organelles, mature red blood cells cannot repair
themselves or synthesize new proteins. They break down after approximately 120 days of
circulation.
---
**Q8. Which organ is primarily responsible for trapping and destroying old, worn-out red blood
cells?**
A) Liver
B) Spleen
C) Kidney
D) Red bone marrow
**Answer: B) Spleen**
**Rationale:** The spleen is often called the "red blood cell graveyard" because its narrow
capillaries trap old, fragile erythrocytes, where splenic macrophages phagocytize them.
---
**Q9. Which part of the hemoglobin molecule directly binds to oxygen?**
A) Globin chain
B) Iron ion in the heme group
C) Biliverdin
| Module 1 Exam Review 70+ Questions and
Answers -Summary | LockDown Browser |
Portage Learning
## SECTION 1: BLOOD COMPOSITION AND PROPERTIES
**Q1. Which component makes up the largest percentage of plasma by weight?**
A) Electrolytes
B) Glucose
C) Proteins
D) Lipids
**Answer: C) Proteins**
**Rationale:** Plasma proteins (albumin, globulins, fibrinogen) constitute about 7-8% of plasma
by weight, making them the largest component by weight after water. They are essential for
osmotic pressure maintenance, transport, and immune function.
---
**Q2. The buffy coat in centrifuged blood contains:**
A) Erythrocytes only
B) Leukocytes and platelets
C) Plasma only
D) All formed elements
**Answer: B) Leukocytes and platelets**
,**Rationale:** When blood is centrifuged, the buffy coat is the thin, whitish layer that forms
between the packed erythrocytes (bottom) and plasma (top). It contains leukocytes (white blood
cells) and platelets (thrombocytes), comprising less than 1% of total blood volume.
---
**Q3. Which of the following is a nitrogenous waste product transported by blood?**
A) Glucose
B) Amino acids
C) Urea
D) Cholesterol
**Answer: C) Urea**
**Rationale:** Urea is a nitrogenous waste product formed in the liver from the breakdown of
amino acids (protein metabolism). Blood transports urea from the liver to the kidneys for
filtration and excretion in urine. Other nitrogenous wastes include uric acid and creatinine.
---
**Q4. Blood temperature is approximately:**
A) 35.0°C (95.0°F)
B) 38.0°C (100.4°F)
C) 37.0°C (98.6°F)
D) 39.5°C (103.1°F)
**Answer: B) 38.0°C (100.4°F)**
**Rationale:** Blood temperature is slightly higher than normal core body temperature,
averaging about 38°C (100.4°F). This is because blood circulation distributes heat generated by
metabolic processes throughout the body, helping to maintain thermal homeostasis.
,---
**Q5. The viscosity of blood is primarily due to:**
A) Plasma water content
B) Erythrocytes and plasma proteins
C) Leukocyte count
D) Electrolyte concentration
**Answer: B) Erythrocytes and plasma proteins**
**Rationale:** Blood viscosity depends mainly on the concentration of erythrocytes (RBCs) and
plasma proteins, especially albumin and fibrinogen. Normal blood viscosity is about 4-5 times
that of water. Increased viscosity (as in polycythemia) increases resistance to blood flow and
cardiac workload.
---
**Q6. Which stem cell gives rise to all formed elements of the blood?**
A) Lymphoid stem cell
B) Myeloid stem cell
C) Hemocytoblast
D) Megakaryocyte
**Answer: C) Hemocytoblast**
**Rationale:** The hemocytoblast is the multipotent hematopoietic stem cell residing in the red
bone marrow that differentiates into all types of blood cells, including erythrocytes, leukocytes,
and platelets.
---
**Q7. What is the average lifespan of a mature erythrocyte in the human body?**
, A) 30 days
B) 60 days
C) 90 days
D) 120 days
**Answer: D) 120 days**
**Rationale:** Due to the lack of a nucleus and organelles, mature red blood cells cannot repair
themselves or synthesize new proteins. They break down after approximately 120 days of
circulation.
---
**Q8. Which organ is primarily responsible for trapping and destroying old, worn-out red blood
cells?**
A) Liver
B) Spleen
C) Kidney
D) Red bone marrow
**Answer: B) Spleen**
**Rationale:** The spleen is often called the "red blood cell graveyard" because its narrow
capillaries trap old, fragile erythrocytes, where splenic macrophages phagocytize them.
---
**Q9. Which part of the hemoglobin molecule directly binds to oxygen?**
A) Globin chain
B) Iron ion in the heme group
C) Biliverdin
