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

[Q]: Passage: CHAPTER SUMMARY 37.1 Types of Hormones There are three basic types of hormones: lipid-derived, amino acid-derived, and peptide. Lipid-derived hormones are structurally similar to cholesterol and include steroid hormones such as estradiol and testosterone. Amino acid-derived hormones are relatively small molecules and include the adrenal hormones epinephrine and norepinephrine. Peptide hormones are polypeptide chains or proteins and include the pituitary hormones, antidiuretic hormone (vasopressin), and oxytocin. Answer: peptide
[A]: There are three basic types of hormones: lipid-derived, amino acid-derived, and what?

[Q]: Passage: Pulmonary circulation is the part of the circulatory system that carries blood between the heart and lungs (the term pulmonary means "of the lungs"). It is illustrated in Figure below . Deoxygenated blood leaves the right ventricle through pulmonary arteries, which transport it to the lungs. In the lungs, the blood gives up carbon dioxide and picks up oxygen. The oxygenated blood then returns to the left atrium of the heart through pulmonary veins. Answer: oxygen
[A]: While in the lungs, blood gives up carbon dioxide and picks up what element before returning to the heart?

[Q]: Passage: Collisions between hydrogen atoms demonstrate one form of nuclear fusion. Answer: nuclear fusion
[A]:
Collisions between hydrogen atoms demonstrate one form of what?