Optometry Admission Test (OAT) Practice

What does growth hormone primarily stimulate?

1. Milk production

2. Pain inhibition

3. Bone and muscle growth, and lipolysis

4. Thyroid hormone production

The correct answer is: Bone and muscle growth, and lipolysis

Growth hormone primarily stimulates bone and muscle growth as well as lipolysis. This hormone, secreted by the pituitary gland, is essential for promoting overall growth and development, particularly in children and adolescents. It enhances the uptake of amino acids by cells, facilitating protein synthesis, which is vital for muscle growth. Additionally, growth hormone plays a significant role in stimulating the liver to produce insulin-like growth factor 1 (IGF-1), further promoting growth in various tissues, including bone. Lipolysis, the breakdown of fats into fatty acids and glycerol, is another crucial function of growth hormone. By facilitating the mobilization of energy stores from fat tissue, growth hormone helps regulate metabolism and maintains energy balance in the body. The other options do not reflect the primary actions of growth hormone. Milk production is associated more with prolactin, pain inhibition involves various neurotransmitters and pathways, and thyroid hormone production is regulated by thyroid-stimulating hormone rather than growth hormone. Understanding these roles underscores the multifaceted impact of growth hormone on growth, metabolism, and overall health.