Evolution Darwins Theory_Unsolved Paper
Chapter: Heredity and Evolution | Topic: Evolution Darwins Theory
EVOLUTION DARWINS THEORY_UNSOLVED PAPER
Topic: Evolution Darwins Theory
Q1.Charles Darwin proposed his theory of evolution mainly on the basis of:
- Natural selection
- Artificial selection only
- Cell division
- Photosynthesis
Q2. According to Darwin, organisms generally produce:
- Exactly the number of offspring that can survive
- More offspring than can survive in the available environment
- Only one offspring during their lifetime
- No offspring when resources are limited
Q3. The struggle for existence occurs mainly because:
- Resources are unlimited
- Organisms require resources that may be limited
- All organisms have identical characteristics
- Organisms do not reproduce
Q4. According to natural selection, individuals with favourable variations are more likely to:
- Survive and reproduce
- Stop reproducing
- Lose all inherited traits
- Become completely identical to other organisms
Q5. Which of the following is most closely associated with Darwin's explanation of evolution?
- Natural selection
- Germ theory
- Law of conservation of mass
- Theory of relativity
Q6. A population contains individuals with different variations. If environmental conditions favour one variation, over generations that variation may:
- Become more common in the population
- Immediately disappear
- Stop being inherited
- Affect every organism equally
Short questions
Q1. What is meant by natural selection according to Darwin's theory?
Q2. Why did Darwin consider variations important in the process of evolution?
Q3. What is meant by the struggle for existence? Why does it occur among organisms?
Q4. How does overproduction of offspring contribute to competition among organisms?
Q5. Imagine a school garden where many plants compete for sunlight, water, and space.
How could differences among the plants affect which ones grow and reproduce more successfully?
Q6. Suppose a population of insects lives in an agricultural field where environmental conditions change over several years.
Why might some insects survive better than others?
Q1. Explain the main ideas of Darwin's theory of natural selection. Include variation, overproduction, struggle for existence, survival of the better-adapted individuals, and reproduction in your answer.
Q2. Explain how natural selection can gradually change a population over many generations. Use a suitable example to describe the process.
Q3. A population of organisms lives in an environment where food becomes scarce. Individuals in the population show different inherited characteristics.
Using Darwin's theory, explain how such environmental conditions could influence the population over several generations.
Q1. A population contains 200 insects. Among them, 50 individuals show a particular inherited variation. After an environmental change, 30 of these 50 individuals survive and reproduce.
a) What percentage of the original population had this variation?
b) What percentage of individuals with this variation survived and reproduced?
Q2. Two groups of organisms are observed after a change in environmental conditions:
a) Calculate the survival percentage for each group.
b) Which group shows the higher survival percentage?
Q3. In a hypothetical population of 400 insects, 25% possess a variation that may help them survive a new environmental condition. After the environmental change, 60% of the insects with this variation survive.