The endocrine system is a network of glands that release hormones into the bloodstream, which help regulate various bodily functions. One of the key glands in the endocrine system is the pituitary gland, often referred to as the 'master gland.' This gland's hormones influence other glands in the system, including those responsible for growth and metabolism. Understanding the roles of these hormones is crucial for comprehending how the endocrine system affects overall health and behavior.

Which of the following hormones is primarily secreted by the pituitary gland and is involved in stimulating growth in the body?