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.

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