The zygote is split into the blastula after fertilization. The three germ layers develop in the blastula, which in some species is a hollow ball of cells, during a process known as gastrulation.
Fertilization :
The majority of animal reproduction is comparable to human reproduction. Additionally, animals create gametes for fusion. Gamete fusion, however, can happen inside or outside of the body.
Type of fertilization :
internal and external fertilization.
How does fertilization work, for insinstance ?
A reproductive technique that involved joining a male and a female germ cell—each with a single, haploid pair of chromosomes—to produce a diploid cell known as a zygote.
Pre-embryo is a collection of blastomeres formed by cleavage divisions.
To learn more about Fertilization refer : https://brainly.com/question/17120789
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