Answer:
c..... mRNA is made from DNA
Humans ferment lactic acid in muscles where oxygen becomes depleted, which is why sometimes if you finish a run and don't stretch soon you have have discomfort. <span />
This is an experiment where the researcher manipulates one variable, and control/randomizes the rest of the variables. It has a control group, the subjects have been randomly assigned between the groups, and the researcher only tests one effect at a time.
They are related because they are all in the same blood or family you breathe in oxygen and remove carbon dioxide the carbon dioxide it helps other stuff in the ecosystem to survive or live so its like this people breathe oxygen while plants breathe carbon dioxide.
