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
In which situation can natural selection make a trait more common?MediumLevel 20Why does the sex of a human child depend on the chromosome coming from the father?MediumLevel 20If a particular inherited trait appears in every generation of a family how can it be studied?MediumLevel 20Which example shows an inherited trait?EasyLevel 20Which example shows an acquired trait?EasyLevel 20In a plant, the yellow-seed trait is dominant over the green-seed trait. If two first-generation plants are crossed, which trait may reappear in the second generation?MediumLevel 20What does the three-to-one ratio in the second generation of a monohybrid cross show?MediumLevel 20Why is variation necessary for evolution?MediumLevel 20If an insect has bark-like colour and escapes predators, which process will this help?MediumLevel 20In which situation can a trait be useful in one environment but not useful in another?MediumLevel 20Why are homologous organs considered evidence of an evolutionary relationship?MediumLevel 20Why are the human arm and bat wing homologous organs?MediumLevel 20Why are the wings of a bird and an insect called analogous organs?MediumLevel 20How do fossils provide evidence for evolution?MediumLevel 20Fossils found in deeper layers of rocks are generally considered signs of what?MediumLevel 20Why can genetic drift have a stronger effect in a small population?MediumLevel 20Which statement shows the correct understanding of evolution?MediumLevel 20Why is it said that evolution does not always mean progress?MediumLevel 20In which situation can a variation pass to the next generation?MediumLevel 20Why is a small error during copying of genetic material not always harmful?MediumLevel 20