Respiration is a process of exchanging gas.
The role of water in the citric cid cycle is that the cycle consumes water and acetate molecules. Hope this helped!
<span>Excess nutrients levels. Can't be sure but that's what I believe. </span>
1. true. natural selection keeps the more suited traits which makes them more adapted to environment (evolving over time).
2. you would expect human DNA to be close to a tiger because they are both mammals.
3. mutations are the raw material for evolution.
4. a cell
5. survive and reproduce
