Long Answer Questions
1. Explain the process of photosynthesis with a word equation.
Answer:
Photosynthesis is the process by which green plants prepare their food using sunlight, water, and carbon dioxide. The equation for photosynthesis is:
Carbon dioxide + Water + Sunlight → Glucose + OxygenPlants absorb carbon dioxide from the air through stomata.
Roots absorb water from the soil and transport it to the leaves.
Chlorophyll in leaves traps sunlight to convert water and carbon dioxide into glucose and oxygen.
2. How do plants obtain nutrients other than carbohydrates?
Answer:
Besides carbohydrates made through photosynthesis, plants absorb minerals like nitrogen, phosphorus, and potassium from the soil through their roots. These minerals help in plant growth, cell repair, and fruit formation. Some plants also depend on insects or symbiotic relationships to obtain additional nutrients.
3. Describe the different modes of nutrition in plants with examples.
Answer:
Plants obtain nutrition in different ways:
Autotrophic nutrition: Plants make their own food through photosynthesis (e.g., sunflower).
Heterotrophic nutrition: Some plants depend on other organisms for food.
Parasitic plants: Depend on a host for nutrients (e.g., Cuscuta).
Saprotrophic plants: Absorb nutrients from decaying matter (e.g., fungi).
Insectivorous plants: Trap and digest insects for nutrients (e.g., Venus flytrap).
4. What are insectivorous plants? How do they get their nutrition?
Answer:
Insectivorous plants grow in nutrient-poor soil, so they trap and digest insects to obtain nitrogen and other nutrients. They have modified leaves, like sticky surfaces or trap mechanisms, to catch prey. Example: Venus flytrap, which closes its leaves when an insect touches it.
5. Explain the symbiotic relationship in plants with an example.
Answer:
A symbiotic relationship is when two different organisms live together and help each other. An example is lichen, a combination of algae and fungi. The algae produce food through photosynthesis, while the fungi provide water and shelter. Another example is Rhizobium bacteria in leguminous plants, which help fix nitrogen in the soil.
6. Why is photosynthesis important for all living beings?
Answer:
Photosynthesis is essential because:
It produces oxygen, which all animals need for breathing.
It provides food for plants, which form the base of the food chain.
It helps maintain the balance of oxygen and carbon dioxide in the atmosphere.
It supports life by supplying energy to all living organisms, directly or indirectly.