Which of the following must be true of the structures of axons and muscle cells in order for nerve impulses to stimulate muscle contraction?

A. Axons in muscle cells must both have structures that make in secrete the same molecules
B. Axons in muscle cells must both have receptors that recognize the same small molecules
C. Axons must have structures that make and secrete molecules in muscle cells must have receptors that recognize these molecules.
D. Muscle cells must have structures that make and secrete molecules in the axons must have receptors that recognize these molecules
I think its D

Disagree

God fast

psydag then whats the answer then

To determine which answer choice is correct, let's break down the requirement for nerve impulses to stimulate muscle contraction.

Nerve impulses are electrical signals transmitted through axons, which are long, slender extensions of neurons. These impulses travel from the nervous system to the muscle cells, initiating muscle contraction. Muscle cells, also known as myocytes, have specialized structures that enable contraction, such as actin and myosin filaments.

For muscle contraction to occur, there needs to be communication between the nerve impulses and the muscle cells. This communication is achieved through the release of certain molecules, specifically neurotransmitters, from the axon terminals. These neurotransmitters bind to receptors on the muscle cell membrane, triggering a series of events that eventually lead to muscle contraction.

Let's analyze each answer choice in relation to this explanation:

A. Axons in muscle cells must both have structures that make and secrete the same molecules.
This answer choice suggests that axons in muscle cells must produce and release the same molecules. However, there is no requirement for axons within muscle cells to produce and secrete any specific molecules. Hence, this choice is incorrect.

B. Axons in muscle cells must both have receptors that recognize the same small molecules.
This answer choice suggests that both axons and muscle cells must possess receptors that recognize the same small molecules. This is not correct because muscle cells do not have receptors for the neurotransmitters released by the axons. Therefore, this choice is not accurate.

C. Axons must have structures that make and secrete molecules, and muscle cells must have receptors that recognize these molecules.
This answer choice correctly describes the process. Axons secrete specific molecules (neurotransmitters), and muscle cells have receptors on their membrane specifically designed to recognize and respond to these molecules. This communication allows nerve impulses to stimulate muscle contraction. Hence, this choice is accurate.

D. Muscle cells must have structures that make and secrete molecules, and axons must have receptors that recognize these molecules.
This answer choice suggests that muscle cells produce and release molecules, and axons have receptors to respond to them. However, this is not accurate because the primary communication occurs through the release of neurotransmitters from axons to muscle cell receptors. Therefore, this choice is incorrect.

In conclusion, the correct answer is C: Axons must have structures that make and secrete molecules, and muscle cells must have receptors that recognize these molecules.

Its C