once an egg has been fertilized,
a zygote is formed
a barrier to other sperm forms immediately
new genes are formed
cytoplasm is always exchanged(can be more than one answer)
the zygote becomes haploid

The answer is a zygote is formed.

In the process called fertilization, the egg cells or so called ovum will fuse with a sperm cell. The result of this fusion leads to the development of the zygote which will then develop to an embryo.

the father in the first generation probably had the recessive colorblind trait in his x chromosome. if he and his wife both had the colorblind trait, even if she had 1 recessive and 1 dominant, then that trait would be passed on to their kids.

(since you didn't attach the family tree this is just an assumption)

answer; both surfaces of the membrane are nonpermeable