The raw material used by plants during photosynthesis

1

(a)

N₂ and O₂

(b)

O₂, H₂, CO₂

(c)

CO₂ and water

(d)

water and minerals

Paheli wanted to buy a gift made of animal fibre obtained without killing the animal. Which of the following would be the right gift for her to buy?

1

(a)

Woollen shawl

(b)

Silk scarf

(c)

Animal fur cap

(d)

Leather jacket

The coldest region on the earth is the

1

(a)

polar region

(b)

tropical region

(c)

temperate region

(d)

coastal region

The word monsoon is derived from the word

1

(a)

mausam

(b)

monsoon

(c)

museum

(d)

storm

The hardest layer of the soil is

1

(a)

The top soil

(b)

The middle layer

(c)

The third layer

(d)

The lower most layer

Sometimes when we do heavy exercise, anaerobic respiration takes place in our muscle cells. What is produced during this process?

1

(a)

Alcohol and lactic acid

(b)

Alcohol and CO₂

(c)

Lactic acid and CO₂

(d)

Lactic acid only

Transport of food in plants takes place through;

1

(a)

Xylem

(b)

Phloem

(c)

Lenticels

(d)

Bark

What is the relation between distance and speed?

1

(a)

Distance = Speed \(\times\) Time

(b)

Distance = Speed/Time

(c)

Distance = Time/Speed

(d)

None of the above

Boojho and Paheli were given one mirror each by their teacher. Boojho found his image to be erect and of the same size, whereas Paheli found her image erect and smaller in size. This means that the mirrors of Boojho and Paheli respectively are

1

(a)

plane mirror and concave mirror

(b)

concave mirror and convex mirror

(c)

plane mirror and convex mirror

(d)

convex mirror and plane mirror

Which of the following is not a forest product?

1

(a)

Gum

(b)

Plywood

(c)

Sealing wax

(d)

Kerosene

Carbon dioxide and .............. synthesize .................

1

(a)

water , Food/Carbohydrates

Wool yielding animals bear ______ on their body.

1

(a)

hair

The warm air is ______ than cold air.

1

(a)

Lighter

Changing of right side to the left side is called _________.

1

(a)

Lateral inversion

The water bearing layer of the earth is_____________________

1

(a)

aquifer

Diarrhoea can be treated by only giving water to the patient.

1

(a) True

(b) False

Condensation of steam is not a chemical change.

1

(a) False

(b) True

The balance between CO₂ and O₂ is maintained by the plants.

1

(a) False

(b) True

The distance-time graph of standing vehicle is a straight line parallel to x-axis.

1

(a) False

(b) True

Where underground sewerage systems and refuse disposal systems are not available, the high cost onsite sanitation system can be adopted.

1

(a) True

(b) False

Tiny pores present on the surface of the leaves are called ..................

1

(a)

Stomata

Why do we wear light coloured clothes when it is hot?

1

(a)

Light coloured clothes of cotton give us a feeling of coldness by reflecting heat.

Define corrosion

1

(a)

Corrosion is the damage of metals due to air and moisture.

Name any two main elements of weather.

1

(a)

Temperature, humidity, wind-speed.

What do you think will happen to the paper?

1

(a)

Paper strip will start floating.

Can you suggest can method to let more rain water percolate and reach the water underground?

1

(a)

Yes. By making small holes more rain water can be percolated.

How many chambers are there in human heart?

1

(a)

There are four chambers in human heart.

Why is convex lens called a converging lens?

1

(a)

Convex lens converges (bends inside) the rays of light passing through it. So it is called as converging lens.

Name the process which maintains the amount of water on earth.

1

(a)

Water cycle.

Contaminated water is a potential health hazard. Name any two diseases that could be caused by consumption of contaminated water.

1

(a)

Jaundice and cholera.

Ruminants such as cows and buffaloes swallow their food hurriedly and then sit restfully and chew their food. Can you reason why?

2

(a)

Sometimes we see that farmers loosen the soil. What is the reason behind it?

2

(a)

What are converging and diverging lens?

2

(a)

1. List the substances which pollute the soil.

   2

   (a)

2. Why chemicals, solvents and insecticides should not be thrown down the drain?

   2

   (a)

1. The swallowed food moves downwards in the alimentary canal. Explain.

   3

   (a)

2. Why should we worry about the conditions and issues related to forest far from us?

   3

   (a)

When a candle burns, both physical and chemical changes occur. Explain.

3

(a)

Describe the function of the heart.

3

(a)

Distinguish between an open circuit and a closed circuit.

3

(a)

What are conductors of heat and insulators? Discuss their practical applications.

5

(a)

1. Explain the water absorbing capacity of soil with the help of an activity.

   5

   (a)

2. (a) Respiratory process occurs in two phases, what are those two major steps of respiration? Describe each one.
   (b) Define the term breathing rate.

   5

   (a)

1. Give the properties of the images formed by the following:
   (i) Plane mirror
   (ii) Concave mirror
   (iii) Convex mirror
   (iv) Concave lens
   (v) Convex lens.

   5

   (a)

2. Explain how the forest act a natural absorber of rain water.

   5

   (a)