Question

Animals can only do respiration; they cannot perform photosynthesis. Plants can perform photosynthesis, but cannot do respiration.

True

False

One way or another, nearly all the carbon in the bodies of plants and animals ends up back in the atmosphere as carbon dioxide.

True False

If humans did not start digging up and burning fossil fuels about 200 years ago, the total amount of atmospheric carbon would have remained roughly the same.

True False

When one burns a hydrocarbon like octane, ethane (see attachment) or methane, each of the carbon atoms and each of the hydrogen atoms in the hydrocarbon combines with oxygen to produce...

• A. carbon dioxide and water vapor
• B. smoke and water vapor
• C. nitrous oxide and carbon dioxide
• D. carbon dioxide and methane

Answer 1

1. The organisms that respire are called animals while those that make food by photosynthesis are called plants.

So the statement is true.

2. If we consider geological time, all the carbon stored in organisms end up as atmospheric carbon dioxide sooner or later.

So the statement is correct.

3. The major cause of the spike in atmospheric carbon dioxide is the use of fossil fuels in the last two centuries.

So the given statement is true.

4. All the hydrocarbons when burnt produce carbon dioxide and water vapor.

So option A is correct.