Question

Plant part which consists of two generations one within the other is?
Germinated seed, embryo, unfertilized ovule, Seed?

Answer 1

Embryo is the answer.

Seed develops from an ovule (consisting integument and nucellus) or megasporangium. Parts of ovule develop a haploid megaspore which grow into haploid female gametophyte. This female gemetophyte develops an egg or oospore. The latter is fertilized by a male gamete and develops into a zygote (2n). The zygote develops into an embryo or new sporophyte. The embryo (2n) is surrounded by female gemetophyte (n), the latter by seed coat (2n). In this way, seed contains three generations locked one within another. Of these, two generations occur within embryo.