CBSE Class 10 Biology Heredity and Evolution
Heredity and VariationGregor Mendel, conducted hybridization experiments on garden peas for seven years to study the inheritance of characters.
Phenotypic ratio for F2 generation in a monohybrid cross is 3:1 whereas in a dihybrid cross this ratio is 9:3:3:1.
Gene is responsible for the formation of proteins that participate in the final expression of a trait.
Evolution and Evidences of EvolutionFossil records and Anatomical similarities of related life forms are two Evidences of evolution.
Homologous organs have the same while analogous organs have different basic structural design and developmental origin.
Fossils are the preserved remains or traces of animals, plants, and other organisms from the remote past.
Mechanism of EvolutionThe evolutionary theory of Lamarck was based on inheritance of acquired traits whereas Darwin's theory was based on natural selection.
Geographical isolation, genetic drift and natural selection lead to the process of speciation.
XY chromosomes are present in human male, while XX chromosomes are present in human female.
Evolution and ClassificationClassification reflects the evolutionary relationship.
Complex traits are likely to have evolved in small steps through natural selection. Evolution cannot be defined as the progress from lower to higher forms.
Evolution can also take place by artificially selecting for certain attributes. All human beings are a single species.