Science — Plants, Animals, Materials & Our World
1. Plants — The Green World
How Plants Make Food (Photosynthesis)
Sunlight + Water + Carbon Dioxide → Food + Oxygen. Leaves are the FOOD FACTORY. The green colour (CHLOROPHYLL) traps sunlight.
Parts of a Plant
- Roots: Anchor. Absorb water and minerals. Carrot and radish STORE food.
- Stem: Transport water UP and food BOTH WAYS.
- Leaves: Make food. Have tiny PORES (stomata) underneath.
- Flowers: Produce SEEDS. Bees and butterflies help pollination.
Types of Plants
Herbs (soft green stems — grass). Shrubs (woody, branches near ground — rose). Trees (tall, thick trunk — mango). Climbers (need support — money plant).
2. Animals — Adaptations
Where Animals Live (Habitats)
| Habitat | Adaptations |
|---|---|
| Desert | Store water. Active at night. Camel: hump, long lashes. |
| Polar | Thick FUR. Blubber (fat layer). Polar bear. |
| Forest | Camouflage. Tree climbing. |
| Ocean | Gills (fish). Streamlined body. |
By What They Eat
- Herbivores (plants). Carnivores (meat). Omnivores (both).
Life Cycles
Butterfly: Egg → Caterpillar → Pupa → Butterfly. METAMORPHOSIS — complete change! Frog: Egg → Tadpole → Adult frog.
3. Human Body — Staying Healthy
Food Groups
- Carbohydrates (energy — rice, bread). Proteins (growth — pulses, eggs, milk).
- Fats (stored energy — oil, nuts). Vitamins & Minerals (protection — fruits, vegetables).
- Water (essential for EVERYTHING). Roughage (fibre — digestion).
Hygiene
- Brush teeth twice. Wash hands before eating. Bathe daily.
- EXERCISE every day. SLEEP 8-10 hours.
4. Matter and Materials
Three States of Matter
Solid (fixed shape — ice). Liquid (takes container shape — water). Gas (fills all space — steam).
Properties of Materials
- Hard (iron) or Soft (cotton). Soluble (dissolves — salt) or Insoluble (sand).
- Transparent (glass), Translucent (frosted glass), Opaque (wood).
5. Force and Motion
Force — A Push or Pull
- Gravity: Earth pulls everything DOWN.
- Friction: Force that SLOWS things down. Walking (shoe grips ground). Brakes on a cycle.
6. The Earth and Our Solar System
- The SUN is a STAR. The Earth is a PLANET.
- Earth ROTATES on its axis → DAY and NIGHT.
- Earth REVOLVES around the Sun → SEASONS (365¼ days).
- The MOON orbits Earth. Phases: New Moon → Crescent → Full Moon.
7. Environment — Protect Our Planet
Pollution
- Air: Smoke from factories and vehicles. Water: Sewage, chemicals. Land: Litter, plastic.
The 3 R's: REDUCE (use less). REUSE (use again). RECYCLE (turn waste into new things).
Conservation
- Save WATER — turn off the tap! Plant TREES. Don't throw PLASTIC.
- 'Every little action COUNTS. YOU can make a difference!'
