NLN NEX EXAM MASTERY QUESTION
BANK WITH VERIFIED ANSWERS
1. Which organelle is responsible for the detoxification of drugs and poisons in the human
liver?
A. Rough endoplasmic reticulum
B. Golgi apparatus
C. Smooth endoplasmic reticulum
D. Lysosomes
Answer: C
Conceptual Explanation: The smooth endoplasmic reticulum is involved in lipid synthesis,
carbohydrate metabolism, and the detoxification of drugs and poisons, particularly in liver
cells.
2. In a standard DNA molecule, which nitrogenous base pairs with Guanine?
A. Adenine
B. Cytosine
C. Thymine
,D. Uracil
Answer: B
Conceptual Explanation: According to Chargaff’s rules, Guanine always pairs with
Cytosine in DNA via three hydrogen bonds.
3. Which of the following blood vessels carries deoxygenated blood from the heart to the
lungs?
A. Superior vena cava
B. Pulmonary vein
C. Aorta
D. Pulmonary artery
Answer: D
Conceptual Explanation: The pulmonary artery is unique because it carries deoxygenated
blood away from the right ventricle of the heart to the lungs.
4. A solution has a pH of 3. How many times more acidic is it than a solution with a pH of 6?
A. 2 times
B. 30 times
C. 1000 times
D. 100 times
, Answer: C
Conceptual Explanation: The pH scale is logarithmic. Each whole number change in pH
represents a ten-fold change in acidity. A difference of 3 (6 minus 3) means 10 to the power
of 3, which is 1000.
5. Which valve prevents the backflow of blood from the left ventricle into the left atrium?
A. Mitral valve
B. Pulmonary valve
C. Tricuspid valve
D. Aortic valve
Answer: A
Conceptual Explanation: The mitral (or bicuspid) valve is located between the left atrium
and left ventricle.
6. What is the main function of the large intestine?
A. Absorption of nutrients
B. Absorption of water and electrolytes
C. Production of bile
D. Chemical digestion of proteins
Answer: B
BANK WITH VERIFIED ANSWERS
1. Which organelle is responsible for the detoxification of drugs and poisons in the human
liver?
A. Rough endoplasmic reticulum
B. Golgi apparatus
C. Smooth endoplasmic reticulum
D. Lysosomes
Answer: C
Conceptual Explanation: The smooth endoplasmic reticulum is involved in lipid synthesis,
carbohydrate metabolism, and the detoxification of drugs and poisons, particularly in liver
cells.
2. In a standard DNA molecule, which nitrogenous base pairs with Guanine?
A. Adenine
B. Cytosine
C. Thymine
,D. Uracil
Answer: B
Conceptual Explanation: According to Chargaff’s rules, Guanine always pairs with
Cytosine in DNA via three hydrogen bonds.
3. Which of the following blood vessels carries deoxygenated blood from the heart to the
lungs?
A. Superior vena cava
B. Pulmonary vein
C. Aorta
D. Pulmonary artery
Answer: D
Conceptual Explanation: The pulmonary artery is unique because it carries deoxygenated
blood away from the right ventricle of the heart to the lungs.
4. A solution has a pH of 3. How many times more acidic is it than a solution with a pH of 6?
A. 2 times
B. 30 times
C. 1000 times
D. 100 times
, Answer: C
Conceptual Explanation: The pH scale is logarithmic. Each whole number change in pH
represents a ten-fold change in acidity. A difference of 3 (6 minus 3) means 10 to the power
of 3, which is 1000.
5. Which valve prevents the backflow of blood from the left ventricle into the left atrium?
A. Mitral valve
B. Pulmonary valve
C. Tricuspid valve
D. Aortic valve
Answer: A
Conceptual Explanation: The mitral (or bicuspid) valve is located between the left atrium
and left ventricle.
6. What is the main function of the large intestine?
A. Absorption of nutrients
B. Absorption of water and electrolytes
C. Production of bile
D. Chemical digestion of proteins
Answer: B
