Which of the following statements about action potentials is correct?A) Action potentials for a given neuron vary in magnitude. B) Action potentials for a given neuron vary in duration. C) Action potentials are propagated down the length of the axon. D) Movement of ions during the action potential occurs mostly through the sodium pump.

Option-C

Explanation:

Action potential refers to the generation of electrical activity due to the influx and efflux of ions in the cell.

The cell which transmits the action potential is known as the neuron and the neuron maintains the membrane potential at -70 mv. The influx of sodium ions causes depolarization when it crosses the threshold value.  

The generated action potential now travels in the neuron through its long tubular structure called an axon.  The axon transmits the signal from the cell body towards the axon terminal and thus is known as the down the axon.

Thus, Option-C is the correct answer.

answer:

the water molecules are transferred from the roots to the stem or top parts of the tall tree because of important properties of water which are adhesion, cohesion and capillary action. cohesion is the property of water molecules keeps water molecules in a combined state by sharing of bonds between them at the atomic level. adhesion allows the interaction of water molecules with other substances or substrate. adhesion will cause the attachment of water molecules to the wall of the vessel (xylem) of the plant. capillary action occurs when the adhesive force to the vessel wall is stronger than the cohesive force between water molecules. capillary action mimics the transfer of water from a tube or pipe. in this way water utilizes its property to transfer water from down to top level of the plant.  

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