Science
Heredity and Evolution
आनुवंशिकता और विकास
This Class 10 Science topic from the chapter “World of Living” explains how traits are passed from parents to offspring through genes and chromosomes. Students explore Mendel’s experiments, dominant and recessive traits, inherited variation, and the basic idea of sex determination in humans. The topic also introduces evolution, showing how variations, natural selection, fossils, and similarities or differences among organisms help us understand the gradual development of life over generations.
Practice questions
If both factors for a trait in an individual are identical, what is that condition called?EasyLevel 21What is the expected ratio of tall and dwarf plants when a heterozygous tall pea plant is crossed with a dwarf plant?MediumLevel 21Why did Mendel choose pea plants for his experiments?MediumLevel 21If only the dominant trait appears in the first generation, what is the correct conclusion about the recessive trait?MediumLevel 21If gene frequencies in a population change suddenly because of small population size, this is an example of what?HardLevel 21According to Lamarck's idea, why was the long neck of the giraffe thought to have developed?MediumLevel 21Weismann's experiment weakened which idea?MediumLevel 21What is the correct basis of Darwin's natural selection?MediumLevel 21What are organs called that evolved from a common ancestor but perform different functions?MediumLevel 21Bird wings and bat wings are examples of which type of organs when their basic bone structure is compared?HardLevel 21Insect wings and bird wings are a more suitable example of which type of organs?MediumLevel 21What general conclusion is drawn from the depth at which fossils are found?MediumLevel 21How do fossils provide evidence for evolution?MediumLevel 21What is the role of reproductive isolation in the formation of a new species?HardLevel 21Why are acquired traits alone not considered the main basis of evolution?HardLevel 21What is a major source of variation in offspring?MediumLevel 21Why is there less variation among offspring in asexual reproduction?MediumLevel 21If a plant has one capital and one small allele for a trait, what type is it?MediumLevel 21What is the correct difference between phenotype and genotype?MediumLevel 21When will wrinkled seeds appear in a cross between two hybrid round-seeded pea plants?HardLevel 21