Class 8 | Science | Ch 10 | Reaching the Age of Adolescence | NCERT Solutions 1. What is the term used for chemical secretions of endocrine glands for changes taking place in the body? Answer: Hormones are chemical substances secreted by endocrine glands. They are the chemical substances which co-ordinate the activities of living organism and their growth. 2. Define … [Read more...] about Chapter 10 Reaching the Age of Adolescence