Solid.
I have to write all this extra stuff to answer ur question on Brainly but that is the answer :)
The answer is excretory system. The function of the excretory system are; to get rid of of wastes,eliminate useless byproducts excreted from cells, eradicate harmful chemical buildups and maintain a steady, balanced chemical concentration in the body.
This increase in volume leads to a decrease in intra-alveolar pressure, creating apressure<span> lower than atmospheric </span>pressure<span>. As a result, a </span>pressure<span> gradient is created that drives air into the </span>lungs<span>. Figure 3. </span>Inspiration<span> and expiration </span>occur<span> due to the expansion and contraction of the thoracic cavity, respectively.
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The Normal Graph has higher increments of increasing and decreasing; the Cold Spring howeverhas increases and decreases at small amounts, but an overall increase.
