Question 1:

The correct answer is B. the brain and the spinal cord.

Here’s why:

The central nervous system (CNS) is anatomically defined as the brain and the spinal cord. Its role is to process and integrate information.

• Receptors (such as sensory receptors in the skin, eyes, ears) are part of the peripheral nervous system (PNS), not the CNS. The PNS also includes nerves and ganglia that connect the CNS to the rest of the body.

Therefore:

• A is incorrect because receptors are not part of the CNS.

• C is incorrect because the spinal cord is part of the CNS, but receptors are not.

• D is incorrect because it incorrectly includes receptors.

So the correct and only accurate option is B.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 2:

The correct answer is A. A nerve is an individual cell.

Here’s why:

• A. A nerve is an individual cell – This is incorrect. A nerve is not a single cell; it is a bundle of many nerve cells (neurones) along with connective tissue and blood vessels. The individual nerve cell is called a neurone.

• B. A nerve is a bundle of cells – This is correct. A nerve consists of many neurones bundled together.

• C. A neurone has one nucleus – This is correct. A typical neurone has a single nucleus located in the cell body (soma).

• D. An impulse passes along a neurone – This is correct. Nerve impulses (action potentials) travel along the axon of a neurone.

Therefore, the incorrect statement is A.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 3:

The correct row is C:

K is the cell body. M is the axon.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 4:

The correct answer is D.

Since this is a motor neurone, it carries signals to effectors. In the context of these options, muscle cells (or a gland) would be found at the terminal end (L) to receive the signal and carry out a response.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 5:

Answer: C. the student's eyes

Reasoning: In this experiment, the stimulus is the green light appearing on the screen. The eyes are the organs that detect this visual stimulus and convert it into electrical impulses.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 6:

Answer: C. the student's brain

Reasoning: The Central Nervous System (CNS) consists of the brain and spinal cord. In a reaction time test involving conscious decision-making, the brain processes the information from the receptors and coordinates the response.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 7:

Answer: B

Reasoning: Sensory neurons carry electrical impulses from the receptor (eyes) to the CNS coordinator (brain). This is represented by arrow B in the flow diagram.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 8:

Answer: D. at Z

Reasoning: In a reflex arc, the relay neurone (Z) is located entirely within the spinal cord. It connects the sensory neurone (X) to the motor neurone (Y).

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 9:

Answer: B. Synapse

Reasoning: A synapse (M) is the tiny gap or junction between two neurones where an electrical impulse is converted into a chemical signal to pass to the next cell.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 10:

The correct answer is C. They are very quick and automatic.

Here’s why:

• Reflex actions are rapid, automatic responses to stimuli that do not involve conscious thought. They occur via a reflex arc (receptor → sensory neurone → relay neurone in spinal cord → motor neurone → effector), which minimizes delay because the signal does not travel all the way to the brain for processing.

Checking the other options:

• A. They are very quick and under conscious control – Incorrect, because reflexes are not under conscious control; they are involuntary.

• B. They are slow and under conscious control – Incorrect; reflexes are quick, not slow, and not conscious.

• D. They are slow and automatic – Incorrect; reflexes are quick, not slow.

Therefore, C is the correct statement.

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.