Diversity in the Living World — NCERT Solutions

Given: Forests are being cut down due to growing population and increasing needs.

How cutting down forests affects our surroundings:

1. Loss of biodiversity: Plants and animals lose their habitat (home), food, and other resources, leading to a decrease in the variety of living organisms.
2. Loss of habitat: Many animals and plants that depend on forests for shelter and food are forced to move or may die.
3. Climate change: Trees absorb carbon dioxide and release oxygen. Cutting trees increases carbon dioxide levels, contributing to global warming.
4. Soil erosion: Tree roots hold the soil together. Without trees, soil gets washed away by rain or blown away by wind.
5. Disruption of water cycle: Forests play an important role in the water cycle. Deforestation can reduce rainfall and lead to droughts.
6. Flooding: Without trees to absorb rainwater, floods become more frequent.
7. Loss of medicinal plants: Many plants used in medicines may be lost forever.

How we can address this challenge:

1. Afforestation: Plant more trees to replace those that have been cut down.
2. Sustainable use of resources: Use wood and forest products wisely and avoid wastage.
3. Use of alternatives: Use recycled paper, bamboo, and other alternatives to reduce dependence on wood.
4. Protected areas: Establish national parks, wildlife sanctuaries, and biosphere reserves to protect forests.
5. Awareness: Educate people about the importance of forests and biodiversity.
6. Government policies: Support and follow laws that protect forests and penalise illegal cutting of trees.
7. Reduce, Reuse, Recycle: Adopt practices that reduce the demand for forest resources.

Conclusion: Cutting forests harms biodiversity and the environment. By planting trees, using resources wisely, and raising awareness, we can protect our forests and biodiversity.

Given: A flowchart related to grouping of plants. (The flowchart image is referenced but cannot be viewed. Based on the chapter content, the flowchart likely classifies plants based on features such as type of venation, root system, or seed type.)

Based on the chapter context, the flowchart most likely classifies plants as:

• Plants with parallel venation → fibrous roots → monocots (Group B)
• Plants with reticulate venation → taproot → dicots (Group A)

Examples of 'A' (Dicot plants — reticulate venation, taproot):

• Hibiscus (Gudhal)
• Mustard
• Chickpea (Chana)
• Kidney beans
• Sadabahar (Periwinkle)
• Radish

Examples of 'B' (Monocot plants — parallel venation, fibrous roots):

• Grass
• Wheat
• Maize
• Lemongrass
• Banana

Conclusion: 'A' represents dicot plants and 'B' represents monocot plants (or vice versa depending on the flowchart). Examples of dicots include hibiscus, mustard, and chickpea; examples of monocots include grass, wheat, and maize.

Given: Raj claims that Gudhal (hibiscus) is a shrub.

Concept used: A shrub is a plant that has many brown woody stems starting to branch very close to the ground. The stems are hard but not as thick as a tree.

Questions Sanjay can ask for clarification:

1. How tall is the hibiscus plant? (Shrubs are generally shorter than trees but taller than herbs.)
2. Is the stem of the hibiscus plant hard or soft? (Shrubs have hard but not very thick stems.)
3. From where do the branches of the hibiscus plant arise — close to the ground or higher up on the stem? (Shrubs branch close to the ground.)
4. Does the hibiscus plant have many stems or just one main stem? (Shrubs often have multiple stems.)
5. Is the stem of the hibiscus plant as thick as a tree trunk? (If not, it is more likely a shrub.)
6. Can the stem of the hibiscus plant be bent easily? (Shrub stems are hard but not as rigid as tree trunks.)

Conclusion: By asking these questions about the height, stem hardness, thickness, and branching pattern of the hibiscus plant, Sanjay can verify whether it is indeed a shrub. Since hibiscus has a hard but not very thick stem, branches arising close to the ground, and is shorter than a tree, it is correctly classified as a shrub.

Given: Group A — Dicot plants with taproot; Group B — Monocot plants with fibrous roots.

Examples:

(a) Other similarities of plants in Group A (Dicots):

• Their leaves show reticulate venation (net-like pattern of veins).
• Their seeds have two cotyledons (the seed splits into two parts).
• They generally have broad leaves.

(b) Other similarities of plants in Group B (Monocots):

• Their leaves show parallel venation (veins run parallel to each other).
• Their seeds have one cotyledon (single, thin cotyledon).
• They generally have long, narrow leaves.

Given: Images of (a) Duck and (b) Pigeon with labelled feet. (Images are referenced but cannot be viewed. The answer is based on known features.)

Differences in the feet of a duck compared to a pigeon (other bird):

Activity the duck can perform using its webbed feet:

• The duck uses its webbed feet as paddles to swim efficiently in water.
• The broad, flat, webbed feet push against the water, helping the duck to move forward in water.
• The duck can also walk on muddy or slippery surfaces near water bodies without sinking.

Conclusion: The duck's webbed feet are an adaptation to its aquatic habitat. The web between the toes acts like a paddle, enabling the duck to swim easily in water. This is different from the pigeon's feet, which are adapted for perching on branches and walking on land.