What is thyroxine produced by, and what is its primary function?

Thyroxine is produced by follicle cells in the thyroid gland. Its primary function is to increase body metabolism. This hormone plays a crucial role in regulating how the body uses energy. It influences metabolic processes, including the conversion of carbohydrates, fats, and proteins into energy, thus driving various bodily functions.

In terms of metabolic effects, thyroxine helps maintain normal growth and development, particularly in tissues that require energy for synthesis and repair. An increase in thyroxine levels can lead to an overall increase in metabolic rate, which can enhance energy levels, heat production, and overall physical efficiency.

The other options involve functions that do not directly pertain to thyroxine or its production site. While the anterior pituitary does regulate other hormones influencing metabolism, it does not produce thyroxine. The pancreas produces hormones related to blood sugar regulation, and the adrenal glands are involved in the stress response, neither of which align with thyroxine's purpose or origin.