One morning, Deepa was sitting in her garden in Bengaluru. She saw a line of tiny ants marching towards a piece of jaggery that had fallen on the ground. A beautiful butterfly sat on a marigold flower nearby. A buzzing bee flew from one flower to another.
"All these little creatures look so different, but Amma says they are all insects," thought Deepa. "What makes them all insects?" Let us find out what insects are and how they grow.
What Are Insects?
Insects are small creatures that have some special features:
1. They have six legs (three pairs).
2. Their body is divided into three parts: the head, the thorax (middle part) and the abdomen (back part).
3. They have a pair of antennae (feelers) on their head that help them smell, touch and find food.
4. Most insects have wings (usually two pairs), but some like ants do not fly.
5. Insects do not have bones inside their body. Instead, they have a hard outer covering called an exoskeleton.
Think about it: A spider has eight legs. Is a spider an insect? Why or why not?
Common Insects Around Us
| Insect | Where We See It | Special Feature |
|---|---|---|
| Ant | On the ground, near food | Lives in colonies, very strong for its size |
| Butterfly | In gardens, near flowers | Has colourful wings, drinks nectar |
| Mosquito | Near stagnant water | Bites and sucks blood, spreads diseases |
| Honeybee | Near flowers, in hives | Makes honey, lives in colonies |
| Grasshopper | In fields and gardens | Has strong back legs for jumping |
| Housefly | Near food and garbage | Spreads germs by sitting on food |
Helpful and Harmful Insects
Helpful insects: Honeybees give us honey and beeswax. Butterflies and bees help flowers by carrying pollen from one flower to another (pollination). Silkworms give us silk. Ladybugs eat harmful insects that damage crops.
Harmful insects: Mosquitoes spread diseases like malaria and dengue, which are common in many parts of India during the monsoon season. Houseflies spread germs. Locusts destroy crops -- farmers in Rajasthan have faced locust attacks that damaged their fields.
Think about it: Why do we see more mosquitoes during the rainy season in India?
Life Cycle of a Butterfly
A butterfly goes through four stages in its life. This change is called metamorphosis.
Stage 1 -- Egg: The mother butterfly lays tiny eggs on a leaf.
Stage 2 -- Larva (Caterpillar): A caterpillar hatches from the egg. It eats leaves and grows bigger.
Stage 3 -- Pupa (Chrysalis): The caterpillar wraps itself in a hard case. Inside, its body changes completely.
Stage 4 -- Adult (Butterfly): A beautiful butterfly comes out of the case, spreads its wings and flies away.
Life Cycle of a Mosquito
A mosquito also goes through four stages: Egg, Larva, Pupa and Adult. The first three stages happen in stagnant water (water that does not move). This is why we should not let water collect in old tyres, pots, coconut shells or flower pots around our homes.
The Silkworm and Silk
The silkworm is actually the larva (caterpillar) of the silk moth. It feeds on mulberry leaves and spins a cocoon of fine silk thread around itself. In India, silk-making (sericulture) is an important industry in states like Karnataka, Andhra Pradesh and West Bengal. The famous Kanchipuram silk sarees and Banarasi silk sarees are made from this silk.
Think about it: Why is the silkworm called a helpful insect even though it is actually a caterpillar?
| Word | Meaning |
|---|---|
| Insect | A small creature with six legs, three body parts and antennae |
| Antennae | Feelers on the head of an insect used for smelling and touching |
| Exoskeleton | The hard outer covering of an insect's body |
| Metamorphosis | The process of change in the life cycle (egg to adult) |
| Larva | The second stage (caterpillar in butterflies, wriggler in mosquitoes) |
| Pupa | The third stage where the insect changes inside a case |
| Sericulture | The rearing of silkworms to produce silk |
Rohan found a small creature in the garden. It had six legs, two antennae and three body parts. Its body had a hard outer covering. "This is an insect!" said Rohan. He counted the legs carefully -- yes, exactly six. It was a beetle.
In her school garden in Jaipur, Ananya found tiny round eggs under a leaf. After a few days, small caterpillars came out and started eating the leaves. The caterpillars grew fat and then became still, forming a hard case (pupa). After about two weeks, colourful butterflies emerged from the cases. Ananya had watched the complete life cycle of a butterfly.
During the monsoon, the health worker in Gopal's village in Odisha asked everyone to empty all containers with stagnant water. She explained that mosquitoes lay their eggs in still water. By removing stagnant water, the village could stop mosquitoes from breeding and prevent diseases like malaria and dengue.
A. Fill in the Blanks
B. Multiple Choice Questions
C. Short Answer Questions
What to do: Go to your school garden or a park near your home. Observe carefully and find five different insects. Write their names and what they were doing in the table below.
| S. No. | Name of Insect | Where Did You See It? | What Was It Doing? |
|---|---|---|---|
| 1 | |||
| 2 | |||
| 3 | |||
| 4 | |||
| 5 |
Which of the insects you found are helpful? Which are harmful? Write below: