(a) Target site

Hormones are produced by endocrine glands and are poured directly into the blood stream where they are carried to the target site. A specific hormone triggers a specific target site and controls its function.

(b) Sweat gland

It is an exocrine gland because it pours its secretion i.e. sweat through a duct. So it is a duct gland.

(c) Hormones

Hormones are secreted by endocrine glands which controls and coordinates our various organs. Mainly sex hormones control the functioning of our reproductive organs thus controls the changes which occur during adolescence.

(d) Puberty

Puberty is the stage where the reproductive period of an adult starts. In this age, they are capable of producing their young ones. This period is marked by the development of some secondary sexual characters which helps us to differentiate between male and female.