Which of the following is true? Group of answer choices In the brain, neurons are more abundant than neuroglia. An action potential never occurs in dendrites. When a neuron is stimulated, Na+ gates open and allow Na+ to exit the cell. In a myelinated fiber, only the initial segment in the trigger zone has voltage-regulated channels. Norepinephrine is a neuropeptide.

18. which statement about cancer is true?

This is the interaction of two organisms where one is and the other is neither nor harmed.

How do temperature and salinity affect deepwater currents? they create changes in wind direction, moving denser water in the same direction as the wind and causing the deepwater circulation patterns found in the ocean. as temperatures and salinity levels of water increase, the water rises to the surface where it creates currents as it moves to colder regions. they create density differences that cause dense deepwater currents to flow toward the equator where they displace less dense, warmer water above them. they equalize the forces on undersea currents caused by the coriolis effect as they replace more dense water with less dense water.