Carbon and Nitrogen Cycles

Why is carbon considered a versatile element?

• It is the least reactive element.

• It can form only one type of compound.

• It is found only in living organisms.

• It can exist in different forms like graphite and diamond.

What are organic molecules?

• Molecules that contain carbon.

• Molecules that contain oxygen.

• Molecules that contain hydrogen.

• Molecules that contain nitrogen.

Tags

CCSS.L.11-12.4

What is a carbon reservoir?

• A process of carbon fixation.

• A type of carbon compound.

• A place where carbon is stored.

• A form of carbon dioxide.

Which process releases carbon dioxide back into the atmosphere?

• Ammonification

• Cellular respiration

• Nitrogen fixation

• Photosynthesis

What is the concern with excessive carbon dioxide in the atmosphere?

• It causes global cooling.

• It is a greenhouse gas that traps heat.

• It depletes the ozone layer.

• It increases oxygen levels.

What is the primary gas in the atmosphere?

• Hydrogen

• Nitrogen

• Carbon dioxide

• Oxygen

How is nitrogen fixed into a usable form for plants?

• By photosynthesis

• By cellular respiration

• By bacteria in the soil or plant roots

• By decomposers

What is ammonification?

• Conversion of ammonia to nitrates

• Conversion of nitrates to nitrogen gas

• Conversion of nitrogen gas to ammonia

• Return of ammonia to the soil by decomposers

What role do DENITRIFYING bacteria play in the nitrogen cycle?

• They convert nitrates and nitrites back into atmospheric nitrogen gas.

• They convert ammonia to nitrates.

• They decompose organic matter.

• They fix nitrogen into ammonia.

What is a potential problem with excessive nitrogen in plant fertilizers?

• It can drain into water bodies and cause an aquatic producer boom.

• It causes plants to stop growing.

• It depletes atmospheric nitrogen.

• It leads to nitrogen deficiency in soil.