Final answer:
T3 and T4 are thyroid hormones that significantly increase the body's metabolic rate, including enhancing ATP production, regulating blood glucose, and increasing heart rate and responsiveness to stress hormones.
Step-by-step explanation:
The hormones T3 (triiodothyronine) and T4 (thyroxine) are endocrine hormones secreted by the thyroid gland that play crucial roles in regulating the body’s metabolism. T3 and T4 are responsible for increasing the rate of metabolism in cells throughout the body, which involves elevating the basal metabolic rate, enhancing mitochondrial ATP production, and stimulating the rate and force of the heartbeat. They also aid in the regulation of blood glucose levels, protein synthesis, and the body’s responsiveness to catecholamines like adrenaline.
The production of T3 and T4 is dependent on the availability of iodine, and their release is controlled by thyroid-stimulating hormone (TSH) from the anterior pituitary gland. T4 is converted into the more potent T3 within target tissues, and together, these thyroid hormones are essential for maintaining various physiological processes and the overall energy level of the body.