Peptide hormones or protein hormones are hormones whose molecules are peptides, or proteins, respectively. The latter have longer amino acids chain lengths than the former. These hormones have an effect on the endocrine system of animals, including humans. Most hormones can be classified as either amino acid–based hormones (amine, peptide, or protein) or steroid hormones. The former are water-soluble and act on the surface of target cells via second messengers; the latter, being lipid-soluble, move through the plasma membranes of target cells (both cytoplasmic and nuclear) to act within their nuclei. The four most biologically active peptides are:
i. Insulin
ii. Oxytocin
iii. Vasopressin
iv. Angiotensin II
Which hormone controls the reabsorption of water in the kidneys?
Answer & explanation
Correct answer: option 1
Vasopressin is secreted by the posterior pituitary. It acts on kidneys and promotes the reabsorption of water and electrolytes from distal tubules. It prevents water loss and dehydration.