Please choose the correct ending to complete the given sentence: Health: [header] How to study the functions of the thyroid hormone in humans [title] Learn about the structure of the thyroid hormone. [step] Thyroid hormone is a derivative of the amino acid tyrosine. It has iodine atoms attached to it.

Ending1: In this form, the thyroid performs certain functions that your body cannot activate naturally. It also acts as a stimulant to make you oversleep, and to cause you to feel tired more often. Ending2: Therefore, its biosynthesis requires iodide ions that must be supplied in the diet in the form of tablets. Otherwise goiter can result in individuals that are deprived of iodine in their diet. Ending3: Its function is to stop blood clots from getting to the thyroid. The thyroid stimulating hormone in humans is located in the adrenal glands. Ending4: The thyroid hormone is responsible for finding the thyroid sugars in the body. The thyroid needs this intermediate source of iodine in order to have access to the various levels of thyroid sugars.

Answer format: ending1/ending2/ending3/ending4