which of the following is not a function of the liver

ATI TEAS 7

TEAS 7 Science Practice Test

1. Which of the following is NOT a function of the liver?

A. nutrient processing
B. blood filtration and detoxification
C. cholesterol and lipoprotein production
D. insulin production and blood sugar regulation

Correct answer: D

Rationale: The correct answer is D. The liver does not produce insulin; instead, insulin is produced by the pancreas. The liver plays a crucial role in regulating blood sugar levels by storing and releasing glucose but does not directly produce insulin. Choices A, B, and C are functions of the liver. Nutrient processing, blood filtration, detoxification, cholesterol, and lipoprotein production are essential roles performed by the liver to maintain overall metabolic balance and health.

2. Autoimmune diseases occur when the immune system mistakenly attacks healthy body tissues. What is a potential cause of autoimmune diseases?

A. Deficiency in essential vitamins and minerals
B. Exposure to environmental toxins
C. Breakdown in immune cell self-tolerance mechanisms
D. All of the above

Correct answer: C

Rationale: Autoimmune diseases result from a breakdown in immune cell self-tolerance mechanisms, leading to the immune system mistakenly attacking healthy body tissues. While deficiencies in essential vitamins and minerals or exposure to environmental toxins can impact overall health, they are not direct causes of autoimmune diseases. Deficiency in essential vitamins and minerals may weaken the immune system, making it more susceptible to various health issues but does not directly cause autoimmune diseases. Exposure to environmental toxins can trigger immune responses, but autoimmune diseases specifically stem from the breakdown of self-tolerance mechanisms within immune cells. Therefore, the correct answer is a breakdown in immune cell self-tolerance mechanisms.

3. If an organism is AB, which of the following combinations in the gametes is NOT possible?

A. AB
B. AA
C. BB
D. AB

Correct answer: B

Rationale: The correct answer is B. If an organism is AB, it indicates that it carries two different alleles. During gamete formation, each gamete receives only one allele from the pair present in the organism. Therefore, in this case, the possible gametes would be 'A' and 'B,' making 'AA' impossible. Choice A, 'AB,' is possible as each gamete can carry one of the alleles from the genotype. Similarly, 'BB' is also possible if one of the alleles separates into a gamete. Choice D, 'AB,' is essentially the same genotype as the organism and is a possible combination in the gametes.

4. What is the main function of valence electrons in chemical bonding?

A. They are responsible for holding the nucleus together.
B. They are involved in forming bonds with other atoms.
C. They determine the element's physical properties.
D. They play no role in chemical reactions.

Correct answer: B

Rationale: Valence electrons are the electrons in the outermost energy level of an atom. These electrons are involved in forming bonds with other atoms, which is crucial for chemical bonding. By participating in bonding, valence electrons determine an atom's ability to form compounds and engage in chemical reactions. Therefore, the primary function of valence electrons is to facilitate the formation of bonds between atoms, making option B the correct answer. Choices A, C, and D are incorrect because valence electrons primarily influence chemical bonding by participating in the formation of bonds between atoms, rather than holding the nucleus together, determining physical properties, or having no role in chemical reactions.

5. In order to verify if a particular drug is responsible for the recovery of individuals with a disorder, what procedure would be most effective in testing its effectiveness?

A. Ensure that neither the subjects nor the investigators know which subjects are given the drug and which are given the placebo.
B. Ensure that the subjects do not know whether they are given the drug or the placebo, but the investigators are aware of who has received the medication.
C. Ensure that the investigators do not know whether they are administering the drug or the placebo, but the subjects do know which they are receiving.
D. Ensure that both the investigators and the subjects have full knowledge of which subjects are getting the drug and which are getting a placebo.

Correct answer: A

Rationale: The most effective procedure in testing whether the drug is responsible for the recovery is to ensure that neither the subjects nor the investigators know which subjects are given the drug and which are given the placebo. This method is known as a double-blind study, which helps eliminate biases and ensures that the results are reliable and not influenced by expectations or beliefs. By keeping both the subjects and investigators unaware of who is receiving the drug or placebo, the study can accurately determine the true impact of the drug on recovery. Choice B is incorrect as it only prevents the subjects from knowing which treatment they are receiving, allowing for potential bias from the investigators. Choice C is also incorrect as it allows for potential bias from the subjects. Choice D is incorrect as full knowledge of treatment allocation can introduce bias and affect the study's validity.