Recapitulation is a bold and influential idea that is particularly associated with Ernst Haeckel though many other biologists also supported it in the nineteenth and early twentieth centuries. According to the theory of recapitulation, the stages of an organism’s development correspond to the species’ phylogenetic history- in a phrase, “ontogeny recapitulates phylogeny.” Each stage in development corresponds to (that is, [...]
Here is an essay on ‘Genetic Variation’ for class 9, 10, 11 and 12. Find paragraphs, long and short essays on ‘Genetic Variation’ especially written for school and college students. Essay on Genetic Variation Essay # 1. Meaning of Genetic Variation: Evolution requires genetic variation. If there were no dark moths, the population could not have evolved from mostly light [...]
Human embryogenesis is the process of cell division and cellular differentiation of the human embryo during early prenatal development. It spans from the moment of fertilization to the end of the 8th week of gestational age, where after it is called a fetus. From One Cell to Blastocyst: A human develops from a single cell called a zygote, which results [...]