<span>Catfish and carp require less oxygen than trout. The mouth of a river usually has less oxygen and the area closer to the source has more oxygen, so since catfish and trout require more oxygen they typically are found at the source.</span>
Answer:
External means on the outside, so it can be something like their fur color. Some other features can be number of legs, if they have wings or not, etc.
Answer:
c
Explanation:
I think because it's not doing any chemical reaction
Explanation:
Mitochondria is called power house of cell as because They are responsible for the release of energy from food.