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Q1. Describe the pitcher plant. Also discuss how the food in the pitcher plant gets digested?

Solution

In the pitcher plant, the lamina (or blade) of the leaf is modified into a hollow tube called pitcher. The leaf apex forms a lid which can open or close the mouth of the pitcher. Inside the pitcher, there are hairs which are directed downwards. When an insect falls in the pitcher, the lid closes automatically. The trapped insect gets entangled in the hair of the pitcher and hence cannot come out. After some time, the insect dies in the pitcher. The walls of the pitcher plant secrete digestive juices which digest the proteins present in the body of insect to form simpler nitrogen compounds (like amino acids). These simpler nitrogen compounds are absorbed by the walls of the pitcher and used by the whole pitcher plant.

Q2. Why do organisms need to take food?

Solution

Organisms need food as it provides energy for various life processes.

Q3. What are the different ways to replenish the soil?

Solution

There are two different ways to replenish the soil. These are: i. Adding fertilisers. ii. Growing leguminous crops.

Q4. What are the conditions required for photosynthesis?

Solution

The conditions required for photosynthesis are water, sunlight, carbon dioxide and chlorophyll.

Q5. What are the functions of nutrients?

Solution

The nutrients enable living organisms to build their bodies, to grow, to repair damaged parts of their bodies and to provide energy to carry out life processes.

Q6. How water and minerals are transported to the leaves?

Solution

The water and minerals are transported to the leaves by the vessels which run like pipes throughout the roots, stems, branches and leaves.

Q7. What would happen if there will be no photosynthesis process?

Solution

In the absence of photosynthesis there would not be any food and oxygen for the survival of living organisms and the life would be impossible on the earth.

Q8. (i) What are the final products of photosynthesis? What happens to them?(ii) Mention some special features in desert plants.

Solution

(i) Glucose and oxygen are the final products of photosynthesis. Glucose is utilized by the plant and extra glucose gets converted into starch which is stored in plants as reserved food material. Oxygen is released through stomata of leaves.(ii) The desert plants have scale or spine like leaves to reduce the loss of water by transpiration. These plants have green stems which carry out photosynthesis.

Q9. How the leguminous crops replenish the soil?

Solution

Leguminous crops have root nodules which contain Rhizobium bacteria that can convert nitrogen gas of air into nitrates. These nitrates mix with the soil and enrich it. Thus, the soil in the soil gets enriched with nitrogen compounds.

Q10. What are the different ways to replenish the soil?

Solution

There are two different ways to replenish the soil. These are: i. Adding fertilisers. ii. Growing leguminous crops.

Q11. What is the function of guard cells?

Solution

The guard cells guard the stomata present on the surface of the leaves and control the movement of air and water in and out of the stomata.

Q12. What is a host plant?

Solution

The plant on which a parasite climbs to derive its nutrition is called the host plant.

Q13. How can we identify Cuscuta?

Solution

Cuscuta plant is identified as yellow tubular structures twining around the stem and branches of the host plant.

Q14. Why is sun the ultimate source of energy?

Solution

The sun is the ultimate source of energy because the solar energy is capture by the leaves and stored in the plant in the form of food.

Q15. What are the functions of nutrients?

Solution

The nutrients enable living organisms to build their bodies, to grow, to repair damaged parts of their bodies and to provide energy to carry out life processes.

Q16. (i) What is symbiosis?(ii) Name one organism in which symbiosis takes place. (iii) How do lichens show symbiotic relationship?

Solution

(i) The living together of two different species of plants as if they are parts of the same plant and help each other in obtaining food is called symbiosis. (ii) Symbiosis occurs in the plants called ‘lichens’. (iii) In lichens, the green coloured plant called ‘alga’ (autotroph) and non- green plant 'fungus' (saprophyte) live together. The fungus holds the alga cells in its mat of web-like hyphae (thin filaments). The fungus plant absorbs the water and mineral salts from the surroundings and supplies them to alga. The alga plant being green prepares the food by photosynthesis and shares it with fungus. Thus, both alga and fungus gain mutually from one another by living together. This is an example of symbiosis.

Q17. How the leguminous crops replenish the soil?

Solution

Leguminous crops have root nodules which contain Rhizobium bacteria that can convert nitrogen gas of air into nitrates. These nitrates mix with the soil and enrich it. Thus, the soil in the soil gets enriched with nitrogen compounds.

Q18. Define nutrition.

Solution

Nutrition is the mode of taking food by an organism and its utilization by the body.

Q19. (i) Explain how the insect gets trapped in the pitcher plant?(ii) How do fungi germinate?

Solution

(i) Inside the pitcher there are hair which are directed downwards. When an insect lands in the pitcher, the lid encloses and the trapped insect gets entangled into the hair.(ii) The fungal spores are generally present in air. When they land on wet and warm things they germinate and grow.

Q20. How do plants absorb nitrogen from the environment?

Solution

Plants cannot absorb nitrogen in the gaseous form. Soil has certain bacteria that convert gaseous nitrogen into soluble form which is absorbed by plants.

Q21. How will you test the presence of starch in leaves?

Solution

Iodine test is performed to show the presence of starch. If the color of the leaf changes to blue-black by adding iodine on it then it indicates the presence of starch.

Q22. What are nutrients?

Solution

The components of food necessary for the body of living organisms are called nutrients.

Q23. How are fungus and roots of a tree living in symbiotic relationship helpful to each other?

Solution

The tree provides nutrient to the fungus and in return, receives help from it to take up water and nutrients from the soil.

Q24. What nutrients do NPK and Urea fertilisers provide to soil in the fields?

Solution

NPK fertiliser provides nitrogen, phosphorus and potassium to the soil in the fields whereas urea provides only nitrogen.

Q25. How the nutrients are replenished in the soil?

Solution

Fertilisers and manures contain plant nutrients such as nitrogen, phosphorous and potassium, etc. So, when fertilisers and manures are added to the soil in the fields, then the soil gets enriched with nutrients like nitrogen, phosphorous and potassium, etc.

Q26. How the nutrients are replenished in the soil?

Solution

Fertilisers and manures contain plant nutrients such as nitrogen, phosphorous and potassium, etc. So, when fertilisers and manures are added to the soil in the fields, then the soil gets enriched with nutrients like nitrogen, phosphorous and potassium, etc.

Q27. What nutrients do NPK and Urea fertilisers provide to soil in the fields?

Solution

NPK fertiliser provides nitrogen, phosphorus and potassium to the soil in the fields whereas urea provides only nitrogen.

Q28. Why is Cuscuta plant called a parasite?

Solution

Cuscuta plant is called a parasite because it does not have chlorophyll and absorbs food material from the host. In this process, it deprives the host of its valuable nutrients. 

Q29. How Cuscuta plant obtain its food?

Solution

Cuscuta does not have chlorophyll. It takes readymade food from the plant on which it climbs.

Q30. What are insectivorous plants?

Solution

Those green plants which obtain their food partly from insects are called insectivorous plants.