you have been asked to help a top nutrition researcher conduct human experiments on vitamin c as the subjects walk into the laboratory you distribute

HESI LPN

HESI PN Nutrition Practice Exam

1. You have been asked to help a top nutrition researcher conduct human experiments on vitamin C. As the subjects walk into the laboratory, you distribute all the vitamin C pill bottles to the girls and all the placebo pill bottles to the boys. What should you have done?

A. Giving all the boys the vitamin C and the girls the placebo, and telling them what they were getting.
B. Distributing the bottles randomly, randomizing the subjects, and telling them what they were getting.
C. Telling the subjects which group they were in, but preventing yourself from knowing the contents of the pill bottles.
D. Preventing yourself from knowing what is in the pill bottles, and distributing the bottles randomly to the subjects.

Correct answer: D

Rationale: The correct approach in a scientific experiment is to prevent yourself from knowing the contents of the pill bottles and distribute them randomly to the subjects. This randomization helps to avoid bias and ensures that the results are not influenced by preconceived notions. Option A is incorrect because it introduces gender bias by assigning pills based on gender. Option B is incorrect as it mentions telling the subjects what they are getting, which could lead to placebo effects. Option C is incorrect as it suggests disclosing group information to the subjects, which can also introduce bias.

2. What is the most effective therapy for maintaining remission of acute lymphoblastic leukemia?

A. Surgery to remove enlarged lymph nodes
B. Long-term chemotherapy
C. Nutritional supplements to enhance blood cell production
D. Blood transfusions to replace ineffective red cells

Correct answer: B

Rationale: The correct answer is B: Long-term chemotherapy. Long-term chemotherapy, specifically with methotrexate, is the most effective therapy for maintaining remission in acute lymphoblastic leukemia. Surgery to remove enlarged lymph nodes (Choice A) is not the primary treatment for leukemia. Nutritional supplements (Choice C) may support overall health but are not the mainstay therapy for maintaining leukemia remission. Blood transfusions (Choice D) are used to address anemia in some cases but are not the primary treatment for maintaining remission in acute lymphoblastic leukemia.

3. What is one benefit of using controls in an experiment?

A. The size of the groups does not matter.
B. The subjects are unaware of the experiment's details.
C. The subjects who are treated are balanced against the placebos.
D. The subjects are similar in all respects except for the treatment being tested.

Correct answer: D

Rationale: The correct answer is D. Controls in an experiment ensure that the subjects are similar in all respects except for the treatment being tested. This allows for a fair comparison between the treatment group and the control group. Choice A is incorrect because the size of the groups is not the primary benefit of using controls. Choice B is incorrect as blinding, not controls, refers to subjects not knowing about the experiment. Choice C is incorrect as it pertains more to randomization than the use of controls.

4. What is a common side effect of the antibiotic tetracycline in children?

A. Discoloration of teeth
B. Increased appetite
C. Elevated blood glucose levels
D. Decreased bone density

Correct answer: A

Rationale: Discoloration of teeth is a well-known side effect of tetracycline, especially when administered to children below 8 years of age. Tetracycline can bind to calcium ions in developing teeth, causing them to become discolored and appear yellow or brown. Increased appetite, elevated blood glucose levels, and decreased bone density are not commonly associated with the use of tetracycline in children, making them incorrect choices.

5. If a group of people consumes an amount of protein equal to the estimated average requirement for their population group, what percentage of people will receive insufficient amounts?

A. 10
B. 25
C. 33
D. 50

Correct answer: D

Rationale: If a group consumes an amount of protein equal to the estimated average requirement, 50% of the people will receive insufficient amounts. The estimated average requirement is the amount of a nutrient that is estimated to meet the requirement of half the healthy individuals in a particular life stage and gender group. Therefore, 50% of the group will not be meeting their individual needs if they are consuming only the average requirement. Choices A, B, and C are incorrect because at the estimated average requirement level, a higher percentage than those values will receive insufficient amounts.