Define

(a) Juvenile phase,

(b) Reproductive phase,

(c) Senescent phase.

(a) Juvenile phase:

It is the period of growth in an individual organism after its birth and before it reaches reproductive maturity.

(b) Reproductive phase:

It is the period when an individual organism reproduces sexually.

(c) Senescent phase:

It is the period when an organism grows old and loses the ability to reproduce.