How do plants and animals help each other in the exchange of gases in the atmosphere?

Draw (a) a leaf, (b) a taproot and (c) a flower, you have studied for Table 7.3.

You are given an iron strip. How will you make it into a magnet?

Name two foods each rich in:
(a) Fats
(b) Starch
(c) Dietary fibre
(d) Protein

A thick coating of a paste of Plaster of Paris (POP) is applied over the bandage on a fractured bone. It becomes hard on drying to keep the fractured bone immobilised. Can the change in POP be reversed?

Tick (√) the statements that are correct.
(a) By eating rice alone, we can fulfill nutritional requirement of our body. ( )
(b) Deficiency diseases can be prevented by eating a balanced diet. ( )
(c) Balanced diet for the body should contain a variety of food items. ( )
(d) Meat alone is sufficient to provide all nutrients to the body. ( )

List all items known to you that float on water. Check and see if they will float on an oil or kerosene.

Name the part of the plant which produces its food. Name this process.

Why can a pace or a footstep not be used as a standard unit of length?

Given below are the names of some objects and materials:
Water, basket ball, orange, sugar, globe, apple and earthen pitcher Group them as:
(a) Round shaped and other shapes
(b) Eatables and non eatables

Name two items that are made from coconut fibre.

How are clouds formed?

Mark 'True' or 'False' for following statements:
(a) Electric current can flow through metals.
(b) Instead of metal wires, a jute string can be used to make a circuit.
(c) Electric current can pass through a sheet of thermo Col.

Classify the objects or materials given below as opaque, transparent or translucent and luminous or non-luminous:

Air, water, a piece of rock, a sheet of aluminium, a mirror, a wooden board, a sheet of polythene, a CD, smoke, a sheet of plane glass, fog, a piece of red hot
iron, an umbrella, a lighted fluorescent tube, a wall, a sheet of carbon paper, the flame of a gas burner, a sheet of cardboard, a lighted torch, a sheet of cellophane, a wire mesh, kerosene stove, sun, firefly, moon.

What is the composition of air?

Fill up the blanks in the following:
(a) The process of changing of water into its vapour is called _________________.
(b) The process of changing water vapour into water is called _________________.
(c) No rainfall for a year or more may lead to _________________ in that region.
(d) Excessive rains may cause _________________.

In which part of a flower, you are likely to find the ovary?

It was observed that a pencil sharpener gets attracted by both the poles of a magnet although its body is made of plastic. Name a material that might have been used to make some part of it.

Would the bulb glow in the circuit shown in Fig. 12.15?

Some changes are listed in the following table. For each change, write in the blank column, whether the change can be reversed or not.

What is sieving? Where is it used?