how does zygote has diploid chromosome?show it i chart
Answers
Explanation:
A zygote is a single cell which is formed after the process of fertilisation.
Fertilisation is a process in which the male gamete fuses with female gamete to form zygote.
If the fertilisation occurs inside the female it's called internal fertilisation and if fertilisation takes place outside the female body it is called external fertilisation.
So talking about ploidy level (no. of copies of complete genome) of a gamete we can infer that they are haploid i.e they have only one set of complete genome because if they are also diploid like other somatic cells (cells which don't participate in reproduction) when they will fuse the resulting zygote will become tetraploid.
If the zygote begins to grow all the cells will be tetraploid which is not possible in case of humans. so before fusion when the gametes are produced inside an individual their diploid genome is halved by the process of meiosis.
This process only occurs in gametes producing glands i.e. testis in male and ovaries in female. so after meiosis the gametes contain only one set of genome. so when they fuse the resulting cell i.e. zygote is diploid because it contains two sets of genome. one from female gamete and another one from male gamete.
