Botany - Reproduction in Organisms Question with Solution | TestHub

External fertilization means male sperm fertilizes the female ovum outside the body. This requires water as a medium so that sperms can swim and reach the ovum. Release of gametes is known as spawning. The main challenge is timing of the release of gametes as this should be at the same time. The next important factor is that before the gametes fuse with each other environmental factors can destroy them. Hence the gametes are produced in large quantities which causes wastage too. This type of fertilization is most common in fishes and amphibians.