What initially causes a nerve impulse? release of enzymes out of the neuron movement of chemicals into the dendrites of the neuron pathogens attacking the dendrites of the neuron red blood cells bathing the neuron

movement of chemicals into the dendrites of the neuron

Explanation:

Nerve impulse occurs when electrical gradient is moved across the plasma membrane of a resting neuron this is done when the neuron receives a chemical signal from another cell or some other type of stimulus. This action potential then travels down the neuron’s axon as an electric current.

Resting potential occurs because of the difference in electrical charge across the plasma membrane of a neuron.

An electrical gradient is maintained by the sodium-potassium pump this is done across the plasma membrane of a neuron when it is not transmitting a nerve impulse this is the resting potential of the neuron.

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.