There are two types of reproduction :
1. Asexual 2. Sexual
Most of the lower organisms reproduce by asexual means which involve only one parent to reproduce. No gametic fusion occurs and no variations are produced in the progeny.
Higher organisms reproduce by sexual method of reproduction. Both the parents of opposite sex are involved in reproducion. Gametic fusion occurs and variations are produced in the progeny.
Humans reproduce sexually.
The reproductive events in humans include gametogenesis, insemination, fertilization, implantation, gestation and parturition.