TASK DEFINITION: Given a scientific passage and an answer, generate a question for the given answer.
PROBLEM: Passage: Carbon doesn't stop there. Living things get energy from food in a process called respiration. This releases carbon dioxide back into the atmosphere. The cycle then repeats. Answer: carbon dioxide

SOLUTION: Living things get energy from food in a process called respiration, which releases what gas back into the atmosphere?

PROBLEM: Passage: The amount of material left over after a certain number of half-lives can be easily calculated. Answer: pheromone

SOLUTION: What term is used to describe a chemical released by an animal that affects the behavior or physiology of animals of the same species?

PROBLEM: Passage: Allergies occur when the immune system makes an inflammatory response to a harmless antigen. An antigen that causes an allergy is called an allergen. Answer: allergies

SOLUTION:
What occurs when the immune system makes an inflammatory response to a harmless antigen?