The hormone "Thyroxine", which regulates carbohydrate, protein, and fat metabolism, is secreted by:

Correct Option

The correct option is

Thyroid

Explanation

The endocrine system comprises various glands that secrete hormones directly into the bloodstream to regulate physiological processes such as metabolism, growth, and development. Specific glands are responsible for synthesizing distinct hormones with targeted functions.

Detailed Analysis

• Thyroid Gland: This gland is located in the neck region and secretes the hormone Thyroxine (tetraiodothyronine). Thyroxine plays a critical role in regulating the basal metabolic rate (BMR) of the body. It controls the metabolism of carbohydrates, proteins, and fats to ensure the optimal balance required for growth and energy production. Iodine is essential for the synthesis of thyroxine.
• Pituitary Gland: Often referred to as the "master gland," it secretes hormones like Growth Hormone (GH) and Thyroid Stimulating Hormone (TSH), which regulate other endocrine glands, but it does not directly secrete thyroxine.
• Adrenal Gland: Located on top of the kidneys, these glands secrete hormones such as adrenaline (epinephrine) and cortisol, which are involved in the stress response and salt balance, not basal metabolism regulation via thyroxine.
• Pancreas: This is a mixed gland that secretes insulin and glucagon, which are primarily responsible for regulating blood glucose levels.

Key Takeaway

Thyroxine is secreted by the thyroid gland and is the primary hormone responsible for regulating the body's metabolism of carbohydrates, proteins, and fats.