Questions: Multiple Select Question Select all that apply Carbon can be recycled by: fermentation of organic molecules. fixation. sequestration of organic molecules. respiration.

The correct answers are:

• fermentation of organic molecules.
• fixation.
• sequestration of organic molecules.
• respiration.

Explanation for each option:

1. Fermentation of organic molecules: Correct. Fermentation is a metabolic process that converts organic molecules, such as glucose, into simpler compounds like ethanol or lactic acid, releasing carbon dioxide in the process. This contributes to the carbon cycle.

2. Fixation: Correct. Carbon fixation is the process by which inorganic carbon (typically in the form of carbon dioxide) is converted into organic compounds by living organisms, primarily through photosynthesis in plants and some bacteria.

3. Sequestration of organic molecules: Correct. Carbon sequestration refers to the process of capturing and storing atmospheric carbon dioxide. This can occur naturally, such as in forests and oceans, or through human activities like carbon capture and storage (CCS) technologies.

4. Respiration: Correct. Respiration is the process by which organisms convert organic molecules (like glucose) into energy, releasing carbon dioxide as a byproduct. This is a key part of the carbon cycle, as it returns carbon dioxide to the atmosphere.

Summary: All the listed processes—fermentation, fixation, sequestration, and respiration—play roles in the recycling of carbon within the ecosystem.