The reduced potential causes hundreds of <u>voltage-gated sodium</u> channels to open on that part of the cell membrane. The depolarization of the cell causes more of <u>voltage-gated sodium </u>channels to open in adjacent parts of the cell membrane. This begins the wave of of <u>depolarization</u> moving down the axon. Depolarization begins at the <u>axon hillock.</u>
Explanation:
When there is no neuron signaling it becomes polarized, termed as resting membrane potential (RMP) at a threshold voltage (around -55 mV), due to the action of the sodium-potassium pump and the potassium leak channels.
When a change in the RMP occurs, depolarization takes place which causes the voltage-gated sodium channels to open and sodium ions rush into the nerve cell which in turn will increase the voltage threshold to nearly around +40 mV and also charges the neuron positive. This depolarization moves down the axon. This increase in threshold stops the sodium influx and opens the potassium channels to rush the potassium out of the cell.
All these actions decrease the membrane potential leading to a wave of depolarization and going back to resting state. Depolarization begins depending upon the potential gradient at the axon hillock.
Answer:
Option A, Start the reaction by absorbing light energy
Explanation:
Chlorophyll is a green color pigment in plant that helps in entrapping sunlight. Being green in color, it absorbs the blue and red light and reflects the green light. The molecules of chlorophyll gains energy from sunlight and then jumps to higher energy levels by the process known as photo excitation. These excited molecules get ionized to further initiate the process of photosynthesis.
Hence, option A is correct.
This is true.
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