Which of the following is not necessary for respiration?
a. cytochromes
b. oxygen
c. flavoproteins
d. a source of electrons
e. quinones

Oxygen

Explanation:

The final electron acceptor in case of respiration is oxygen. The whole complex consists of many electron acceptor which cannot be substituted.

The first step of cellular respiration is glycolysis and oxygen is not required during this process.

In case of anaerobic respiration, the final electron acceptor is not electron. So here also oxyygen is not required in this process.

Hence, the correct answer is oxygen.

well first you need the sample of the temperature and gas level. i couldnt write a hypothesis unless i had some data. i think temperature changes will effect volumes of gas because gas changed into a solid or liquid at specific temperatures.