Question

Pick one early developmental process (fertilization, cleavage, gastrulation or any axis specification) and COMPARE and CONTRAST this process between one INVERTEBRATE model organism with one VERTEBRATE model organism.

Answer 1

One typical example of invertebrates is silkworm i.e Bombyx mori and one typical example of vertebrates is humans i.e Homo sapiens Let us compare the two:

Fertilisation in silkworm	Fertilisation in human
Spermatozoa is introduced into copulatory opening of female.	Sperms are introduced into the female genital tract of the female.
After few hours, the spermatozoa makes their way through ductus seminalis into common oviduct.	The spermatozoa makes their way towards fallopian tubes through the uterus followed by capacitation of sperms.
The mated female lays eggs; egg is pushed through ovipore.	Humans are viviparous in nature; eggs are retained within the female reproductive system.
Multiple eggs are generated which remains waiting above the single fertile one.	Only one egg is generated in response to ovulation which occurs every month in the reproductve cycle of humans.
The eggs at this point remains diploid. Meiosis starts when sperm enters the egg through micropyle.	Meiosis already takes place before fertilisation. The union of two haploid gametes i.e the sperm and the egg essentially unites to form the diploid zygote.