Answer the question at the bottom.?

Question

An atom of carbon enters a plant as CO2. A cow eats the plant. Explain IN DETAIL what happens to the carbon atom from the time it enters the plant to the time it leaves the cow. Include both photosynthesis and cellular respiration in your explanation.

Answer 1

This question is impossible to answer completely in this format. There are too many details and too many alternatives depending upon what the plant is and which path inside the cow that the chewed plant takes.

The Carbon dioxide enters most plants through the stomata on the undersides of the leaves. The CO2 makes its way to the chloroplast of the cells where the Light Dependent Processes (Light Reactions) have made the ATP and NADPH required for the Light Independent Processes (Dark Reactions) can fix the Carbon dioxide using Ribose biphosphate.

The product of this reaction end up as two molecules of 3-phosphoglycerate (only one of which contains the new carbon). This process starts the Calvin-Benson cycle, the final product of which is glucose.

The glucose is usually used to form cellulose for plant growth or a starch for food storage. This is the form that the carbon enters the cow.

Cellulose will probably go through the cow much like it will in humans: as fiber or roughage. Starch can be broken down by digestion using enzymes like amylase to get the glucose molecules back.

The glucose released can make its way into the cells of the cow where cellular respiration can take place. The glucose is used in the Krebb's cycle to generate ATP. The last site below shows only the most important parts of the Krebb's cycle.