What is the primary function of thyroxine?

Thyroxine, a hormone produced by the thyroid gland, plays a crucial role in regulating the body's metabolism. It helps control the rate at which the body converts food into energy, influencing how efficiently the body uses calories. By increasing the metabolic rate, thyroxine impacts various bodily functions, such as temperature regulation, heart rate, and overall energy levels.

This hormone has a vital role in growth and development and is essential for maintaining proper physiological functions. Conditions associated with imbalances of thyroxine can lead to issues such as hypothyroidism or hyperthyroidism, where metabolic processes are significantly altered.

The other functions listed in the options are not directly related to thyroxine. For instance, while digestion is stimulated by other hormones and mechanisms, it does not fall under the primary actions of thyroxine. Similarly, blood sugar levels are regulated primarily by insulin and glucagon, and stress responses involve hormones like cortisol and adrenaline rather than thyroxine.