I need help with this ecology question

The finches on the galapagos island were similar in form except for variations of their beaks. darwin observed that these variations were useful for: attracting a mate defending territory building nests gathering food

Match the description of each organism to the appropriate category

Photosynthesis uses co2 and cellular respiration produces co2. we call the point when the two processes are in balance--when there is no net production of co2--the compensation point. how might you limit one of the processes in order to achieve a compensation point?