Evolution Question 33

33. Which one of the following statement is correct?

[2007]

(a) There is no evidence of the existence of gills during embryogenesis of mammals

(b) All plant and animal cells are totipotent

(c) Ontogeny repeats phylogeny

(d) Stem cells are specialize cells.

Show Answer

Answer : c

Hints & Solution

(c) Ontogeny repeats phylogeny. The theory of recapitulation, also called the biogenetic law or embryological parallelismoften expressed using Ernst Haeckel’s phrase “ontogeny recapitulates phylogeny”-is a historical hypothesis that the development of the embryo of an animal, from fertilization to gestation or hatching (ontogeny), goes through stages resembling or representing successive adult stages in the evolution of the animal’s remote ancestors (phylogeny). It was formulated in the 1820 s by Étienne Serres based on the work of Johann Friedrich Meckel, after whom it is also known as Meckel-Serres law.