The majority of genes in the human beings are same and the variation lies in some point percentage. This small percentage causes a huge variation in the phenotype of the humans. The expression of gene is different in different individuals. The variation is very tiny though this little variation leads to a large phenotypic variation and makes one individual different from other.
Embryonic development involves process of formation and development of an embryo. In humans, during the early stages, 10 weeks of embryonic development, all the major body organs are formed.
