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In humans, the medulla region of the brain is mainly responsible for the regulation process of respiration. It is also called the respiratory rhythm centre. The chemosensitive area located near the respiratory centre sends signals across nerve impulses to alter the rate of expiration to eliminate compounds.
The answer Would Be B
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<span>Substances can move into and out of cells through the cell membrane. The three main types of movement are diffusion, osmosis and active transport.</span>