which of the following about the autonomic nervous system ans is true

ATI TEAS 7

ATI TEAS Science

1. Which of the following statements about the autonomic nervous system (ANS) is true?

A. It controls involuntary functions
B. It contains motor (efferent) neurons
C. It contains sensory (afferent) neurons
D. It contains both parasympathetic and sympathetic nerves

Correct answer: D

Rationale: The correct answer is D because the autonomic nervous system (ANS) is responsible for controlling involuntary functions and contains both parasympathetic and sympathetic nerves. Choices A and B are incorrect as they do not fully capture the role of the ANS. While the ANS does control involuntary functions, this is a broader concept than just the reflex arc. While the ANS does contain motor (efferent) neurons, it also includes sensory (afferent) neurons, which are not specifically mentioned in the question. Therefore, choice C is not fully accurate. Choice D provides the most accurate and comprehensive description of the autonomic nervous system by highlighting its components, the parasympathetic and sympathetic nerves, which work together to regulate various bodily functions.

2. Which hormone is responsible for lowering blood sugar levels?

A. Glucagon
B. Insulin
C. Adrenaline
D. Cortisol

Correct answer: B

Rationale: Insulin is the hormone responsible for lowering blood sugar levels. It is produced by the pancreas and facilitates the entry of glucose into cells, thereby reducing blood sugar levels. Glucagon, adrenaline, and cortisol have roles in increasing blood sugar levels through various mechanisms. Glucagon raises blood sugar levels by stimulating the liver to release stored glucose, adrenaline increases blood sugar in fight-or-flight responses, and cortisol raises blood sugar levels as part of the stress response. Therefore, in the context of lowering blood sugar levels, insulin is the correct answer.

3. Photons, the basic unit of light, are:

A. Charged particles
B. Packets of energy with wave-particle duality
C. Electromagnetic waves only
D. Always absorbed by matter

Correct answer: B

Rationale: Photons are not charged particles; they are packets of energy that exhibit wave-particle duality, meaning they can behave as both particles and waves. While photons are part of the electromagnetic spectrum, they are not electromagnetic waves themselves but rather discrete energy packets. They are not always absorbed by matter; they can be reflected, transmitted, or scattered.

4. Which of the following correctly describes mitosis?

A. Mitosis occurs in germ cells.
B. Mitosis occurs in somatic cells.
C. Mitosis involves the reduction of chromosome number by half.
D. Mitosis produces four genetically different cells.

Correct answer: B

Rationale: The correct answer is B. Mitosis occurs in somatic cells where a single cell divides to produce two identical daughter cells. Germ cells undergo meiosis, not mitosis. Choice C is incorrect as mitosis results in the preservation of the same chromosome number in daughter cells. Choice D is inaccurate as mitosis produces genetically identical cells, not genetically different ones.

5. In a food chain, which trophic level captures energy from the sun?

A. Decomposers
B. Carnivores
C. Producers
D. Omnivores

Correct answer: C

Rationale: Producers, such as plants, algae, and some bacteria, are the organisms in a food chain that capture energy from the sun through the process of photosynthesis. They convert sunlight into chemical energy, which is then passed on to other organisms in the food chain. Producers are at the base of the food chain and form the foundation for all other trophic levels to obtain energy. Decomposers (option A) break down organic matter, carnivores (option B) consume other animals, and omnivores (option D) consume both plants and animals, but they do not directly capture energy from the sun.