When does a farmer prefer asexual or sexual methods of reproduction for crops production? Class 9
When does a farmer prefer asexual or sexual methods of reproduction for crops production? Class 9
Think It Over (Page 208)
Question 1.
When does a farmer prefer asexual or sexual methods of reproduction for crops production? Class 9
Answer:
A farmer prefers asexual methods of reproduction when: They want to produce genetically identical plants that reliably carry desirable traits (e.g., high yield, disease resistance, specific taste or fruit quality). They want to propagate plants quickly without waiting for seeds to germinate. They want to grow plants that do not produce seeds easily or whose seeds take a long time to germinate (e.g., banana, sugarcane, potato).
A farmer prefers sexual methods of reproduction when: They want to develop new varieties with improved traits by crossing two varieties (hybridisation). They want to produce seeds for large-scale cultivation of crops like wheat and rice. They want to introduce variation and adaptability into crops to help them survive changing environmental conditions or diseases.
Question 2.
Why do you think most complex animals and flowering plants use sexual reproduction, while many simple organisms, like yeast and hydra mainly reproduce asexually? Class 9
Answer:
Most complex animals and flowering plants use sexual reproduction because it creates genetic variation in offspring. Variation is important for survival in complex, changing environments. It allows populations to adapt to new diseases, climate changes, and other environmental pressures over time, ultimately contributing to evolution. Simple organisms like yeast and hydra mainly reproduce asexually because: Asexual reproduction is faster and more energy- efficient.
These organisms live in relatively stable environments where variation is not as critical. Asexual reproduction allows for rapid population increase when food and conditions are favourable. Being simple organisms, they do not need the complexity of finding a mate or forming specialised reproductive organs.