Final answer:
Normal human fertilization requires the acrosomal reaction, zygote formation, cleavage, and implantation.
Step-by-step explanation:
Normal human fertilization requires the following processes:
- Acrosomal reaction: This is a process where the sperm releases digestive enzymes to penetrate the protective layer of the egg, called the zona pellucida.
- Zygote formation: Fusion of a sperm and egg forms a zygote, a single diploid cell.
- Cleavage: The zygote undergoes rapid cell division called cleavage, resulting in the formation of a solid ball of cells known as a morula.
- Implantation: The blastocyst, a fluid-filled ball of differentiated cells, attaches to the uterine wall during implantation.
- This reaction involves the release of digestive enzymes from the acrosome of the sperm, enabling it to attach to, and burrow through to the egg's plasma membrane, where it can release its haploid nucleus. The fusion of the haploid nuclei of the sperm and egg results in the formation of a diploid zygote.
- Therefore, the correct answer is b) Acrosomal reaction, as it precedes zygote formation, cleavage, and implantation, which are subsequent stages of embryonic development following fertilization.