Answer
The hormone being secreted to excess by the anterior pituitary is growth hormone(GH).
It is the hormone that stimulates growth and metabolism
Work Step by Step
Johnny's abnormally fast rate of growth is due to abnormally high amounts of growth hormone( somatotropin) being secreted and released into his blood stream by an anterior pituitary tumor.
The following are some of the normal actions of growth hormone: it stimulates cell growth in every organ, increases protein synthesis, and decreases protein degradation. In addition GH improves calcium retention, increases bone mineralization, and increases metabolic rates.