Diversity in the Living World — Solutions
All 10 in-text Activities and all 10 “Let us enhance our learning” exercise questions, answered in detail — using the same figures printed in the textbook.
On their nature walk with Dr Raghu and Maniram chacha, the students discover how plants and animals differ — and how those differences let each one survive in its own habitat. Every activity table and every numbered question below is worked through step by step.
Activity Solutions (2.1 – 2.10)
Model answers, completed sample tables and explanations for every activity in the chapter.
Let us explore and record
You were asked to:
- Go on a nature walk and observe plants, insects, birds and other animals.
- Record features of stems, leaves and flowers in Table 2.1, and habits of animals in Table 2.2.
| S. no. | Local name | Stem | Leaves (shape/arrangement) | Flowers | Other observations |
|---|---|---|---|---|---|
| 1 | Common grass | Soft and thin | Single leaf grows alternately from different points | — | Green leaves |
| 2 | Tulsi | Hard and thin | Pair of leaves in opposite directions | Pinkish purple | — |
| 3 | Hibiscus | Hard | Broad, pointed tip, net-like veins | Large, red, bell-shaped | Attracts butterflies |
| 4 | Neem | Hard and thick | Leaves with smooth surface | Small, white, fragrant | — |
| 5 | Rose (any other) | Hard, thin, thorny | Oval, toothed edges | Red/white/pink, fragrant | Thorns on stem |
| Animal | Place they live | Food they eat | How they move | Other observations |
|---|---|---|---|---|
| Crow | Tree | Insects | Fly and walk | Carries a twig in its beak |
| Ant | Nest in soil/burrow | Leaves, seeds, insects | Walks | Has six legs |
| Cow | Open fields, sheds | Grasses, leaves | Walks on four legs | Chews cud |
| Sparrow (any other) | Bushes, rooftops | Grains, insects | Fly, hop and walk | Builds small nests |
Similarities/differences among plants: stems differ in height (tall/short) and hardness (hard/soft); leaves differ in shape and arrangement; flowers differ in colour, shape and scent.
Similarities/differences among animals: some live on land, some on trees, some in water, and some (like frogs) in both; they eat different foods and move in different ways.
Let us appreciate
You were asked to:
- Picture one plant and one animal you have closely observed, and draw them with your classmates.
- Discuss how many different plants/animals the whole class drew, and whether more varieties exist.
My picks: a marigold flower and a sparrow.
Class observation: Even in a class of 30 students, hardly any two students draw the exact same plant and animal — some draw a rose, a mango tree, a butterfly, a dog, a fish, and so on. A typical class might end up with 15–20 different plants and animals on the board.
Are there more varieties than those drawn? Yes — definitely. What ends up on the board is only a tiny sample of what actually exists. There are lakhs of plant and animal species around the world (and thousands even in one city), so the board only shows a small glimpse of true biodiversity.
Let us group
You were asked to:
- Collect pictures of plants and animals, and group the cards based on common features with your classmates.
- Compare your grouping basis with other groups in the class.
My group used “hard stem vs soft stem” to sort the plant cards, and “where they live” (land / water / both) to sort the animal cards. Another group in class used “presence or absence of flowers” for plants and “what they eat” for animals instead.
Let us group
You were asked to observe plant height, stem colour/hardness, and where branches arise, and fill Table 2.3.
| Plant | Height | Stem colour | Tender/Hard | Thick/Thin | Branches | Group |
|---|---|---|---|---|---|---|
| Mango | Tall | Brown | Hard | Thick | Higher up | Tree |
| Rose | Medium | Brown | Hard | Thin | Close to ground | Shrub |
| Tomato | Short | Green | Tender | Thin | Close to ground | Herb |
| Neem | Tall | Brown | Hard | Thick | Higher up | Tree |
| Hibiscus | Medium | Brown | Hard | Thin | Close to ground | Shrub |
| Common grass | Short | Green | Tender | Thin | Close to ground | Herb |
Differences among trees, shrubs and herbs:
- Trees — very tall, hard/thick/brown woody stem, branches high up (e.g. mango, neem).
- Shrubs — medium height, hard but thinner woody stem, many branches close to the ground (e.g. rose, hibiscus).
- Herbs — short, soft green stem, delicate (e.g. tomato, grass).
Plants with weak stems that need support to climb are climbers; plants that spread along the ground are creepers.
Let us compare
You were asked to look at collected leaves and notice variation in the pattern of veins (venation).
Leaves show two main venation patterns:
- Reticulate venation — a net-like pattern of veins on both sides of a thick middle vein. Example: hibiscus.
- Parallel venation — veins run parallel to each other along the length of the leaf. Example: banana, grass.
Yes — plants can be grouped on the basis of their leaf venation, into those with reticulate venation and those with parallel venation.
Let us find out
You were asked to dig out a few wild herbs carefully, wash and observe their roots, then replant them.
- Taproot — one thick main root with thinner side roots branching off it. Example: mustard, hibiscus.
- Fibrous root — a bunch of similar, thin roots arising from the base of the stem, with no single main root. Example: grass, wheat.
Let us relate and analyse
You were asked to collect five saplings, observe their roots and leaf venation, and record them in Table 2.4.
| S. no. | Plant | Leaf venation | Root type |
|---|---|---|---|
| 1 | Lemongrass | Parallel | Fibrous |
| 2 | Marigold | Reticulate | Taproot |
| 3 | Sadabahar (periwinkle) | Reticulate | Taproot |
| 4 | Wheat | Parallel | Fibrous |
| 5 | Chickpea (chana) | Reticulate | Taproot |
Let us compare
You were asked to soak chickpea and maize seeds, remove the chickpea’s seed coat, and compare the structure of both seeds.
The chickpea seed splits into two equal parts (cotyledons), while the maize seed has just one thin cotyledon.
- Dicotyledons (dicots) — two cotyledons; reticulate leaf venation; taproot system. Example: chickpea.
- Monocotyledons (monocots) — one cotyledon; parallel leaf venation; fibrous root system. Example: maize.
Let us find out
You were asked to list animals and note the way each one moves and which body parts it uses, in Table 2.5.
| Animal | Type of movement | Body parts used |
|---|---|---|
| Ant | Walks and crawls | Legs |
| Goat | Walks and jumps | Legs |
| Pigeon | Walks and flies | Legs and wings |
| Housefly | Walks and flies | Legs and wings |
| Fish | Swims | Fins |
| Snake | Slithers/crawls | Whole body (muscles) |
| Earthworm | Crawls | Whole body (muscles) |
| Frog | Hops/jumps and swims | Legs |
Let us compare and analyse
You were asked to list plants and animals found in the desert, mountains, ocean, forest, and other regions, in Table 2.6.
| Desert | Mountains | Ocean | Forest | Any other (Grassland) |
|---|---|---|---|---|
| Camel | Deodar tree | Fish | Lion | — |
| Cactus | Rhododendron | Whale | Monkey | Zebra |
| Scorpion | Snow leopard | Coral | Deer | Grasses |
Why do plants and animals of one region differ from another? Because each region has different conditions (temperature, water, soil, wind) — plants and animals develop special features, called adaptations, that let them survive there.
- Desert plants (like cactus) have fleshy, water-storing stems to survive heat with little water.
- Deodar trees have a conical shape with sloping branches so snow slides off easily.
- The hot-desert camel has long legs and wide hooves (walks on sand without sinking) and one hump; the cold-desert (Ladakh) camel has shorter legs, two humps, and long hair for the cold.
Exercise Question Solutions (Q1 – Q10)
Direct, detailed answers to every question from the end-of-chapter exercise.
Wheat vs Kidney beans
| Feature | (a) Wheat | (b) Kidney beans |
|---|---|---|
| Seed type | Monocot (one cotyledon) | Dicot (two cotyledons) |
| Root type | Fibrous root | Taproot |
| Leaf venation | Parallel venation | Reticulate venation |
Group animals by habitat
A — Aquatic only
- Dolphin
- Whale
C — Both (Amphibious)
- Frog
- Crocodile
- Tortoise
B — Terrestrial only
- Horse
- Sheep
- Squirrel
- Earthworm
- Pigeon
Note: Crocodiles and tortoises spend time both in water and on land, so they fit part C along with frogs, even though they are reptiles and not classified as amphibians biologically.
Manu’s radish
A radish is a taproot — it is a single, thick, fleshy main root that grows straight down into the soil (this swollen taproot is the part we eat), with thin lateral roots branching off it.
Since radish has a taproot, its leaves would show reticulate (net-like) venation — following the same pattern seen in other taproot plants such as mustard and hibiscus.
Mountain goat vs plains goat
Similarities: both are goats with four legs, horns, and hooves; both eat grass and leaves; both are terrestrial (land) animals.
Differences: the mountain goat has thick, long, shaggy white fur, while the plains goat has short, thin fur in mixed colours.
Reason: these are adaptations to their habitats. The mountain goat’s thick woolly coat keeps it warm in the cold, snowy mountains and often blends with snow (camouflage). The plains goat lives in warmer conditions, so a short coat is enough and helps it stay cool.
Group by a new feature
Basis chosen: whether the animal can fly.
Group 1 — Can fly
- Pigeon
- Bat
- Cockroach
- Grasshopper
Group 2 — Cannot fly
- Cow
- Tortoise
- Whale
- Fish
- Lizard
Deforestation and biodiversity
Effects of cutting down forests:
- Plants and animals lose their habitat — their source of food, water and shelter — leading to a loss of biodiversity (some species may even disappear from that region, or go extinct).
- Less vegetation means less oxygen production and more pollution; it can also affect rainfall patterns.
- Soil is no longer held together by roots, so it can be washed or blown away (soil erosion), sometimes causing landslides or floods.
- Removal of natural predators/prey can disturb the balance of the whole ecosystem.
How we can address it:
- Plant more trees and support afforestation drives.
- Use forest resources responsibly and avoid unnecessary cutting.
- Support and follow government conservation projects (like Project Tiger) and protected/sacred grove areas.
- Spread awareness, sign petitions, and support community movements — just like the successful Save Silent Valley Movement mentioned in this chapter.
Analyse the flowchart
A = plants with reticulate venation, i.e. dicots — examples: hibiscus, mustard, chickpea, rose.
B = plants without reticulate venation (i.e. with parallel venation), i.e. monocots — examples: wheat, maize, grass, banana.
Raj and Sanjay’s argument
To verify Raj’s claim, Sanjay could ask questions that check the features that define a shrub:
- How tall is the plant — is it short, medium, or as tall as a tree?
- Is the stem hard/woody or soft and green?
- Is the stem thick (like a tree) or comparatively thin?
- From where do the branches arise — close to the ground, or higher up on a single main stem?
- Does the plant have multiple woody stems branching near the base, rather than one single trunk?
If the hibiscus plant is medium height with a hard but thin stem, branching close to the ground, then it does fit the definition of a shrub.
Dicot and monocot examples
| Group | Type of seed | Type of root | Examples |
|---|---|---|---|
| A | Dicot | Taproot | Mustard, chickpea (gram), hibiscus, mango, rose |
| B | Monocot | Fibrous roots | Wheat, maize, grass, banana, lemongrass |
(a) Other similarities in Group A (dicots): two cotyledons in the seed; leaves show reticulate (net-like) venation.
(b) Other similarities in Group B (monocots): a single cotyledon in the seed; leaves show parallel venation.
Duck’s webbed feet
The duck’s feet have skin stretched between the toes, forming a paddle-like “webbed” shape. A pigeon’s feet have separate, thin toes with no skin joining them.
These webbed feet act like paddles and let the duck swim efficiently in water — pushing more water back with each stroke — which is why ducks (unlike pigeons) are so much at home both on land and in ponds or lakes.
Quick pointers for the project tasks
These are open-ended, hands-on class projects rather than questions with fixed answers — here’s how to get started on each.
- Indian biodiversity scientist report — pick one name (e.g. Janaki Ammal or Salim Ali, both introduced in this chapter) and note their field of work, one major achievement, and one place/species they helped protect.
- Divya Mudappa, Usha Lachungpa, Ghazala Shahabuddin, Nandini Velho, Vidya Athreya, Uma Ramakrishnan, Divya Karnad — choose any three; look up which ecosystem or species each works on (e.g. rainforests, snow leopards, tigers, marine life) and summarise their contribution in 3–4 lines each.
- Label school plants — walk around your school with your teacher/gardener, note down the local name of at least 8–10 plants, and record them in your notebook.
- Class biodiversity register — after a nature walk, combine every student’s Table 2.1/2.2 style observations into one master class list — this is a great group project for updating Activity 2.1.
- Project Tiger presentation — cover: why it started (1973, declining Bengal Tiger population), what it does (protected tiger reserves), and one or two success numbers you can find, plus similar projects like the Cheetah Reintroduction Project (2022).
- Family interview on changing biodiversity — ask grandparents/neighbours which birds, insects or plants they remember seeing often as children that are rarer now (and vice versa) — this connects directly to how habitat damage causes loss of biodiversity, discussed on Pg. 28.