which of the following is a characteristic of an interneuron

ATI TEAS 7

ATI TEAS Practice Science Test

1. Which of the following is a characteristic of an interneuron?

A. Forms neural circuits
B. Interacts with effectors
C. Sends impulses to the CNS
D. Functions as an efferent nerve cell

Correct answer: A

Rationale: The correct characteristic of an interneuron is that it forms neural circuits, connecting sensory and motor neurons within the central nervous system. Interneurons facilitate communication between different neurons in the central nervous system, helping in the processing and integration of signals. Choice B is incorrect as interneurons primarily interact with other neurons, not effectors. Choice C is incorrect as interneurons typically do not send impulses to the CNS; they operate within the CNS. Choice D is incorrect as interneurons are not efferent nerve cells; they are mainly involved in processing signals within the CNS rather than transmitting signals to effectors.

2. Which hormone, produced by the thyroid gland, plays a key role in regulating calcium levels in the blood by promoting calcium release from bones and increasing calcium reabsorption in the kidneys?

A. Calcitonin
B. Parathyroid hormone (PTH)
C. Thyroxine
D. Insulin

Correct answer: A

Rationale: Calcitonin, produced by the thyroid gland, is responsible for regulating calcium levels in the blood. It works by decreasing blood calcium levels through two main mechanisms: promoting calcium uptake by bones and decreasing calcium reabsorption in the kidneys. Parathyroid hormone (PTH), on the other hand, increases blood calcium levels by promoting calcium release from bones and increasing calcium absorption in the intestines. Thyroxine, another thyroid hormone, primarily regulates metabolism and has no direct influence on calcium levels. Insulin, produced by the pancreas, is involved in regulating blood sugar levels and is not related to calcium homeostasis.

3. What are organisms that break down dead organisms and return nutrients to the environment called?

A. Producers
B. Decomposers
C. Consumers
D. Parasites

Correct answer: B

Rationale: Decomposers are essential organisms in the ecosystem as they break down dead organisms and organic matter, such as bacteria, fungi, and some insects. By decomposing complex organic materials into simpler forms, they release nutrients back into the environment for other organisms to utilize. Producers (option A) are organisms that generate their own food through photosynthesis; consumers (option C) are organisms that feed on other organisms for energy, and parasites (option D) are organisms that live on or in another organism, benefiting at the host's expense rather than breaking down dead organisms for nutrient recycling.

4. What type of immunity is acquired through vaccination?

A. Passive natural immunity
B. Active natural immunity
C. Active artificial immunity
D. Passive artificial immunity

Correct answer: C

Rationale: The correct answer is C, Active artificial immunity. Vaccination introduces a weakened or inactive form of the pathogen to stimulate the immune system, leading to the development of immunity. Active artificial immunity is the result of deliberate exposure to an antigen, such as through vaccination, to produce an immune response. Passive immunity, like receiving pre-formed antibodies, does not involve the immune system's activation. Natural immunity is typically acquired through exposure to the pathogen itself, not through vaccination.

5. What is the term for a solution with a pH value less than 7?

A. Acidic
B. Neutral
C. Alkaline
D. Basic

Correct answer: A

Rationale: Solutions with a pH less than 7 are classified as acidic. pH values below 7 indicate an acidic solution, which means it has a higher concentration of hydrogen ions. Choices B, C, and D are incorrect as they describe neutral (pH 7), alkaline (pH greater than 7), and basic (another term for alkaline), respectively, which are not applicable to solutions with a pH less than 7.