Question

Explain why a human zygote is more likely to grow into an adult than a frog zygote.

Answer 1

In humans, fertilisation is internal. The zygote divides and forms the embryo which is implanted in the uterus. This embryo receives all the nutrients and care from the mother's body and develops into an adult.

In frogs, fertilisation is external and the zygote is formed outside the body. Thus, it forms a larva instead of developing directly into an adult.