What is formed by the fusion of male and female gametes?

When the cleavage furrow extends from the animal pole to the vegetal pole and does not bisect the egg equally into two blastomeres,the plane of cleavage is:

The fusion of a sperm with which of the following results in the formation of a diploid zygote?

Sperm enters from which part of the egg?

Which reproductive adaptation is characteristic of most terrestrial vertebrates but not of most aquatic vertebrates?

Fertilization takes place in