Chapter 2: Diversity in the Living World

The two types of seeds shown are a dicot seed (like chickpea) and a monocot seed (like maize).

Roots:

• Dicot seed plant → has a taproot system (one main root with small side roots)
• Monocot seed plant → has a fibrous root system (a bunch of thin, similar-sized roots)

Leaf Venation:

• Dicot seed plant → shows reticulate venation (net-like pattern of veins)
• Monocot seed plant → shows parallel venation (veins run parallel to each other)

So, the number of cotyledons in a seed is linked to both the type of root and the type of leaf venation the plant will have.

A – Aquatic (live in water):

• Dolphin
• Whale

B – Terrestrial (live on land):

• Horse
• Sheep
• Squirrel
• Earthworm
• Pigeon

C – Both aquatic and terrestrial (amphibious/semi-aquatic):

• Frog
• Crocodile
• Tortoise

Frogs, crocodiles, and tortoises can survive both in water and on land, so they belong to group C. Dolphins and whales are fully aquatic animals that live in the ocean.

Radish is a taproot — it has one main thick root (which we eat) with small side roots growing from it, making it a modified taproot system.

Since radish is a dicot plant, its leaves show reticulate venation, meaning the veins form a net-like pattern on both sides of a thick middle vein.

This is consistent with the general rule: dicot plants have taproots and reticulate venation in their leaves.

Similarities:

• Both are goats with four legs, hooves, and similar body structures
• Both are herbivores (plant-eating animals)
• Both use legs for movement

Differences:

Feature	Mountain Goat	Plains Goat
Body fur	Thick and dense	Thin and less dense
Legs/hooves	Strong, sturdy, adapted for rocky terrain	Suitable for flat ground
Body size	Generally more compact	May vary

Reasons for differences: These differences are adaptations to their respective habitats. Mountain goats need thick fur to survive cold temperatures and strong hooves to grip rocky mountain surfaces. Plains goats do not need these features as their environment is warmer and the ground is flat. The habitat shapes the features of animals over time.

One way to group these animals is based on whether they have a backbone (vertebrates) or no backbone (invertebrates):

Group 1 – Animals WITH a backbone (Vertebrates):

• Cow, Pigeon, Bat, Tortoise, Whale, Fish, Lizard

Group 2 – Animals WITHOUT a backbone (Invertebrates):

• Cockroach, Grasshopper

Another way could be grouping by number of legs:

• No legs: Whale, Fish
• Two legs: Pigeon, Bat
• Four legs: Cow, Tortoise, Lizard
• Six legs: Cockroach, Grasshopper

The backbone grouping is a clear and valid scientific way to classify these animals.

Effects of cutting down forests:

• Animals lose their habitats (homes, food, and shelter), leading to a decline in their populations
• Biodiversity decreases as many plants and animals may become endangered or extinct
• Cutting trees leads to soil erosion, floods, and changes in rainfall patterns
• The amount of oxygen in the air decreases since trees produce oxygen through photosynthesis
• Climate change worsens as trees help absorb carbon dioxide

How we can address this challenge:

• Plant more trees (afforestation) to replace those that are cut
• Reduce, reuse, and recycle materials to lessen the demand for forest resources
• Use alternative materials instead of wood wherever possible
• Support and follow government projects like Project Tiger and protected area programmes
• Raise awareness in the community about the importance of forests
• Learn from traditional practices like sacred groves, where communities protect forest patches

Protecting forests means protecting biodiversity and ensuring a healthy planet for all living beings.

Based on the plant grouping flowchart in the chapter, which likely classifies plants based on the number of cotyledons in their seeds:

• 'A' (Dicot plants – two cotyledons, reticulate venation, taproot): Examples include chickpea (chana), mustard, hibiscus (Gudhal), rose, mango
• 'B' (Monocot plants – one cotyledon, parallel venation, fibrous roots): Examples include maize (corn), wheat, rice, grass, banana

Dicot plants have two seed leaves (cotyledons) and show reticulate venation, while monocot plants have one cotyledon and show parallel venation. This relationship between seed type, venation, and root type is a key basis for this grouping.

Sanjay can ask the following questions to verify whether hibiscus is a shrub:

1. How tall is the hibiscus plant? (Shrubs are shorter than trees but taller than herbs)
2. Is the stem of the hibiscus hard or soft? (Shrubs have woody but not very thick stems)
3. From where do the branches of the hibiscus plant start? (Shrub branches start close to the ground)
4. Is the stem thin like a herb or thick like a tree? (Shrub stems are moderately hard but not as thick as tree trunks)
5. Does the plant have many stems arising from near the ground? (Shrubs often have multiple woody stems branching close to the ground)

Based on these features — woody stems, branching near the ground, and moderate height — hibiscus is indeed classified as a shrub.

Based on the grouping criteria from the chapter (type of stem, venation, root type, and cotyledon number), here are examples for each group:

Group	Features	Examples
Herbs	Small, soft green stem	Tomato, wheat, coriander, grass
Shrubs	Medium height, woody branching near ground	Rose, hibiscus (Gudhal), tulsi
Trees	Tall, thick woody stem, branches high up	Mango, neem, deodar, banyan
Dicots	Two cotyledons, reticulate venation, taproot	Chickpea, mustard, sunflower, mango
Monocots	One cotyledon, parallel venation, fibrous roots	Maize, wheat, rice, banana, grass

These examples are drawn from the plants discussed in the chapter as well as common plants found in everyday life.

Difference in duck's feet: Ducks have webbed feet — the toes are connected by a thin skin/membrane. Most other birds (like sparrows or pigeons) have separate, claw-like toes without any webbing between them.

Activity the duck can perform: The webbed feet act like paddles, helping the duck to swim efficiently in water. When the duck pushes its feet backward in water, the webbing spreads out and pushes more water, propelling the duck forward.

This is a clear example of adaptation — the duck's webbed feet are specially suited to its aquatic habitat, allowing it to move easily in water.