Question

multiple choice 20 points
how do photosynthesis and cellular respiration work together in the carbon and oxygen cycle?
both processes release oxygen in to the atmosphere.
respiration produces oxygen while photosynthesis produces carbon dioxide.
photosynthesis uses carbon dioxide and releases oxygen while respiration uses oxygen and releases carbon dioxide.
photosynthesis releases carbon dioxide and respiration uses oxygen to make sugar.
multiple choice 20 points
what role do nitrogen - fixing bacteria play in the nitrogen cycle?
they remove nitrogen from the soil.
they release nitrogen gas into the atmosphere.
they convert nitrogen gas into a form of nitrogen plants can use.
they break down dead plants and animals.

Explanation:

• For the first question:
• Photosynthesis equation: \(6CO_{2}+6H_{2}O

ightarrow C_{6}H_{12}O_{6}+6O_{2}\) (uses \(CO_{2}\), releases \(O_{2}\)).

• Cellular respiration equation: \(C_{6}H_{12}O_{6}+6O_{2}

ightarrow6CO_{2}+6H_{2}O\) (uses \(O_{2}\), releases \(CO_{2}\)).

• For the second question:
• Nitrogen - fixing bacteria convert atmospheric \(N_{2}\) (which plants can't use directly) into ammonia (\(NH_{3}\)) or other nitrogen - containing compounds that plants can absorb.

Answer:

1. C. Photosynthesis uses carbon dioxide and releases oxygen while respiration uses oxygen and releases carbon dioxide.
2. C. They convert nitrogen gas into a form of nitrogen plants can use.