Why does anaerobic respiration occurs after aerobic respiration an athlete's body?​

Explanation:

As the athlete works harder, their body uses more and more oxygen. Eventually, the body is not able to keep up with the the oxygen demand, thus it switches to anaerobic respiration temporarily. Anaerobic respiration does not use oxygen and thus is used after the body cannot supply oxygen quick enough.

hey bro i looked it up on google the structure of the eye-spot in euglena viridie, e. ehrenbergii, and phacus pyriyorme is not as franzé haa described it. the so-called “crystal body” and “lens bodies” were not found in any of the individuals of the species examined by me. as earlier observers have stated, the eye-spot consists simply of a mass of pigment granules arranged in a single layer, and probably embedded in a protoplasmic framework, but the latter could not be seen, and its presence was only inferred from the fact that the pigment granules must be held together in some way, thd the eye-spot as a whole is capable of expansion, and that the pigment granules can be separated from each other.

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the correct answer is:

a population changes in response to a change in the environment.