1. Which of the following is the primary function of red blood cells?
A) Immune defense
B) Oxygen transport
C) Blood clotting
D) Fluid balance
Answer: B) Oxygen transport
Rationale: The primary function of red blood cells (RBCs) is to transport oxygen from the lungs
to tissues and carbon dioxide from tissues to the lungs. RBCs contain hemoglobin, a protein that
binds oxygen.
2. The right ventricle pumps blood into which vessel?
A) Aorta
B) Pulmonary artery
C) Pulmonary veins
D) Superior vena cava
Answer: B) Pulmonary artery
Rationale: The right ventricle pumps deoxygenated blood into the pulmonary artery, which
carries it to the lungs for oxygenation.
3. What is the role of the sinoatrial (SA) node in the heart?
A) Initiates electrical impulses that regulate the heartbeat
B) Stimulates the atrioventricular (AV) node
C) Pumps blood to the lungs
D) Regulates blood pressure
Answer: A) Initiates electrical impulses that regulate the heartbeat
Rationale: The SA node, located in the right atrium, generates electrical impulses that initiate
the heartbeat and set the pace for the heart.
4. The autonomic nervous system controls all of the following except:
A) Heart rate
B) Respiratory rate
C) Voluntary muscle movement
D) Digestion
Answer: C) Voluntary muscle movement
Rationale: The autonomic nervous system regulates involuntary functions such as heart rate,
, digestion, and respiratory rate. Voluntary muscle movement is controlled by the somatic nervous
system.
5. Which of the following is the main function of the kidneys?
A) Hormone production
B) Filtration of waste from the blood
C) Oxygen transport
D) Regulation of body temperature
Answer: B) Filtration of waste from the blood
Rationale: The kidneys filter metabolic waste products from the blood, maintain electrolyte
balance, and regulate fluid volume and blood pressure.
6. Which part of the brain is primarily responsible for regulating balance and
coordination?
A) Cerebrum
B) Cerebellum
C) Medulla oblongata
D) Hypothalamus
Answer: B) Cerebellum
Rationale: The cerebellum is responsible for motor control, coordination, and balance. It ensures
smooth, coordinated movements.
7. The endocrine glands secrete hormones directly into which system?
A) Nervous system
B) Circulatory system
C) Lymphatic system
D) Muscular system
Answer: B) Circulatory system
Rationale: Endocrine glands release hormones directly into the bloodstream, allowing them to
travel throughout the body to regulate various functions.
8. Which of the following structures is part of the digestive system?
A) Trachea
B) Diaphragm
A) Immune defense
B) Oxygen transport
C) Blood clotting
D) Fluid balance
Answer: B) Oxygen transport
Rationale: The primary function of red blood cells (RBCs) is to transport oxygen from the lungs
to tissues and carbon dioxide from tissues to the lungs. RBCs contain hemoglobin, a protein that
binds oxygen.
2. The right ventricle pumps blood into which vessel?
A) Aorta
B) Pulmonary artery
C) Pulmonary veins
D) Superior vena cava
Answer: B) Pulmonary artery
Rationale: The right ventricle pumps deoxygenated blood into the pulmonary artery, which
carries it to the lungs for oxygenation.
3. What is the role of the sinoatrial (SA) node in the heart?
A) Initiates electrical impulses that regulate the heartbeat
B) Stimulates the atrioventricular (AV) node
C) Pumps blood to the lungs
D) Regulates blood pressure
Answer: A) Initiates electrical impulses that regulate the heartbeat
Rationale: The SA node, located in the right atrium, generates electrical impulses that initiate
the heartbeat and set the pace for the heart.
4. The autonomic nervous system controls all of the following except:
A) Heart rate
B) Respiratory rate
C) Voluntary muscle movement
D) Digestion
Answer: C) Voluntary muscle movement
Rationale: The autonomic nervous system regulates involuntary functions such as heart rate,
, digestion, and respiratory rate. Voluntary muscle movement is controlled by the somatic nervous
system.
5. Which of the following is the main function of the kidneys?
A) Hormone production
B) Filtration of waste from the blood
C) Oxygen transport
D) Regulation of body temperature
Answer: B) Filtration of waste from the blood
Rationale: The kidneys filter metabolic waste products from the blood, maintain electrolyte
balance, and regulate fluid volume and blood pressure.
6. Which part of the brain is primarily responsible for regulating balance and
coordination?
A) Cerebrum
B) Cerebellum
C) Medulla oblongata
D) Hypothalamus
Answer: B) Cerebellum
Rationale: The cerebellum is responsible for motor control, coordination, and balance. It ensures
smooth, coordinated movements.
7. The endocrine glands secrete hormones directly into which system?
A) Nervous system
B) Circulatory system
C) Lymphatic system
D) Muscular system
Answer: B) Circulatory system
Rationale: Endocrine glands release hormones directly into the bloodstream, allowing them to
travel throughout the body to regulate various functions.
8. Which of the following structures is part of the digestive system?
A) Trachea
B) Diaphragm
