Given a scientific passage and an answer, generate a question for the given answer.

Input: Consider Input: Passage: Amphibians have permeable skin that easily absorbs substances from the environment. This may explain why they seem to be especially sensitive to pollution. Monitoring the health and survival of amphibians may help people detect pollution early, before other organisms are affected. Answer: amphibians

Output: What group of animals has permeable skin that makes them vulnerable to pollution?

Input: Consider Input: Passage: Saturated fatty acids have only single bonds between carbon atoms. As a result, the carbon atoms are bonded to as many hydrogen atoms as possible. In other words, the carbon atoms are saturated with hydrogens. Saturated fatty acids are found in fats. Answer: saturated

Output: Carbon atoms are bonded to as many hydrogen atoms as possible in what type of fatty acids?

Input: Consider Input: Passage: After the blood in the pulmonary capillaries becomes saturated with oxygen, it leaves the lungs and travels to the heart. The heart pumps the oxygen-rich blood into arteries, which carry it throughout the body. Eventually, the blood travels into capillaries that supply body tissues. These capillaries are called peripheral capillaries . Answer: to the heart
Output: After the blood in the pulmonary capillaries becomes saturated with oxygen, it leaves the lungs and travels where?