which of the following describes a reflex arc

ATI TEAS 7

ATI TEAS Science Practice Test

1. Which of the following describes a reflex arc?

A. The storage and recall of memory
B. The maintenance of visual and auditory acuity
C. The autoregulation of heart rate and blood pressure
D. A stimulus and response controlled by the spinal cord

Correct answer: D

Rationale: Choice D correctly describes a reflex arc. A reflex arc is a neural pathway that controls a reflex action. It involves a specific sequence of events that occur in response to a stimulus, which is rapidly and involuntarily processed by the spinal cord. The spinal cord coordinates the quick processing of sensory input and the generation of a motor response without involving the brain, allowing for rapid protective responses. Choices A, B, and C are incorrect because they do not accurately describe a reflex arc. A reflex arc is specifically related to the rapid and involuntary response to a stimulus through neural pathways involving the spinal cord, not memory storage, visual and auditory acuity maintenance, or heart rate and blood pressure autoregulation.

2. A researcher wants to investigate the relationship between family income and quality of medical care. Which statement provides the best reason to conduct this investigation?

A. The researcher can identify affordable medical care to recommend to low-income families.
B. The investigation can help identify individuals who are healthy so they can maintain their health.
C. Results of this investigation may identify a group of people who do not receive quality medical care and could benefit from improved medical treatments.
D. There is a valid reason to conduct this investigation.

Correct answer: C

Rationale: The correct answer is C because identifying a group of individuals who do not receive quality medical care can lead to targeted interventions to improve their access to better medical treatments. This investigation can help address disparities in healthcare and improve outcomes for those in need. Choice A is incorrect because the focus is on identifying those who lack quality medical care, not just affordable care. Choice B is incorrect as it misinterprets the purpose of the investigation, which is to improve medical care for those not receiving quality care, rather than maintaining the health of those already healthy. Choice D is too vague and does not provide a specific reason for conducting the investigation, unlike choice C which highlights the potential benefits of identifying individuals in need of improved medical treatments.

3. Which statement accurately defines power?

A. Power is the amount of energy stored in an object
B. Power is the rate at which energy is transferred or work is done
C. Power is the maximum force exerted by an object
D. Power is the resistance of an object to change in motion

Correct answer: B

Rationale: Power is defined as the rate at which energy is transferred or work is done. It is a measure of how quickly work is done or energy is transferred. Option A incorrectly refers to the amount of energy stored in an object, not power. Option C incorrectly refers to the maximum force exerted by an object, not power. Option D incorrectly refers to the resistance of an object to change in motion, not power. Therefore, the correct definition of power is that it is the rate at which energy is transferred or work is done.

4. Which of the following is NOT a function of the lymphatic system?

A. Removing substances from the blood.
B. Releasing hormones.
C. Combating disease.
D. Maintaining tissue fluid balance.

Correct answer: B

Rationale: The correct answer is B. Releasing hormones is not a function of the lymphatic system. The lymphatic system plays crucial roles in removing substances from the blood, combating disease through the production of immune cells, and maintaining tissue fluid balance by circulating lymph. Releasing hormones is primarily the function of endocrine glands, not the lymphatic system.

5. In nuclear physics, the term 'barn' is a unit commonly used to quantify:

A. Energy
B. Radioactivity
C. Nuclear cross-section
D. Half-life

Correct answer: C

Rationale: In nuclear physics, the term 'barn' is a unit used to quantify nuclear cross-section. Nuclear cross-section is a measure of the probability of a nuclear reaction occurring when an atomic nucleus interacts with a particle or another nucleus. The barn is a unit of area equal to 10^-28 square meters; it is commonly used to describe the cross-sectional area of atomic nuclei for nuclear reactions. Choice A, 'Energy,' is incorrect because a barn is not a unit for measuring energy; it is a unit of area. Choice B, 'Radioactivity,' is incorrect as radioactivity is typically measured in units like becquerels. Choice D, 'Half-life,' is also incorrect as half-life is a measure of the time it takes for half of a substance to decay, not related to the concept of a barn as a unit of nuclear cross-section.