MICROANATOMY

Detailed explanation-1: -T3 and T4 are released by the thyroid in response to thyroid-stimulating hormone produced by the anterior pituitary, and both T3 and T4 have the effect of stimulating metabolic activity in the body and increasing energy use.

Detailed explanation-2: -Because the thyroid hormones T3 and T4 control cellular metabolism throughout the body, when there is not enough of them for any reason, this metabolic function slows and becomes impaired.

Detailed explanation-3: -Thyroid cells are the only cells in the body which can absorb iodine. These cells combine iodine and the amino acid tyrosine to make T3 and T4. T3 and T4 are then released into the blood stream and are transported throughout the body where they control metabolism (conversion of oxygen and calories to energy).

Detailed explanation-4: -The hormones leptin and insulin, sex hormones and growth hormone influence our appetite, metabolism (the rate at which our body burns kilojoules for energy), and body fat distribution.

Detailed explanation-5: -The main job of the thyroid is to control your metabolism. Metabolism is the process that your body uses to transform food to energy your body uses to function. The thyroid creates the hormones T4 and T3 to control your metabolism. These hormones work throughout the body to tell the body’s cells how much energy to use.