By heating (melting wax, cooking food).

By mixing with another substance (mixing cement with water).

By applying force (shaping clay).

Expansion: Increase in size on heating (e.g., metals expand).

Contraction: Decrease in size on cooling.

Parts of a Plant:
- Root System: Underground part.
  - Tap Root: Main single root with smaller lateral roots (carrot, radish).
  - Fibrous Root: Cluster of roots originating from the base of the stem (grass, wheat).
  Functions: Anchor plant, absorb water and minerals.
- Shoot System: Part above the ground.
  - Stem: Supports branches, leaves, flowers, transports water and food.
  - Leaves: Site of photosynthesis, transpiration.
    - Venation: Pattern of veins on the leaf.
      - Reticulate: Net-like.
      - Parallel: Parallel veins.
    - Transpiration: Loss of water from leaves in the form of vapour.
  - Flowers: Reproductive part of the plant.
    - Sepals: Protect the bud.
    - Petals: Often brightly coloured.
    - Stamens: Male part.
    - Pistil: Female part.
Types of Plants:
- Herbs: Small, non-woody stems (mint, spinach).
- Shrubs: Medium-sized, woody stems branching near the ground (rose).
- Trees: Tall, strong woody stems (mango, neem).
- Creepers: Plants with weak stems that spread on the ground (pumpkin).
- Climbers: Plants with weak stems that take support and climb up (money plant).

Movement: Change in position of a part of the body.
Locomotion: Movement of the entire body from one place to another.
Skeletons: Framework of bones that provides shape, support, and protection.
- Human Skeleton: Made of bones and cartilage.
  - Bones: Hard, rigid structures.
  - Cartilage: Softer, elastic tissue (e.g., ear).
  - Joints: Place where two or more bones meet.
    - Ball and Socket Joint: Allows movement in all directions (shoulder, hip).
    - Pivotal Joint: Rotational movement (neck).
    - Hinge Joint: Back and forth movement (knee, elbow).
    - Fixed Joint: No movement (skull bones).
Muscles: Attached to bones, contract and relax to cause movement. Muscles work in pairs.
Movement in Animals:
- Earthworm: Body segments expand and contract.
- Snail: Muscular foot produces wave-like movements.
- Cockroach: Three pairs of legs for walking, two pairs of wings for flying.
- Birds: Hollow bones, strong muscles, adapted wings for flight.
- Fish: Streamlined body, strong m