An ecosystem consists of all the things interacting with each

other in a specific geographical area. They can be living or non-

living. Some examples of non-living things that support life in an

ecosystem are light, air, soil, and water. Living things are the

organisms (plants and animals) that use the non living or the

other living things as resources.

All living and non living things are interlinked to each other. Plants

use sunlight to make their food. Some organisms depend on

plants for their food, they are called primary consumers. Some

organisms depend on primary consumers they are called

secondary consumers, so on and so forth.

Given is a diagram known as food chain. Look at it and answer a few questions.

03Iken Scientifica 2011 | Question Set D02 Iken Scientifica 2011 | Question Set D

? 4. Rudder is a device used to steer a boat in a certain direction.

The river is flowing with extreme force downstream. Bob and

Sam have not reached the other shore. What should be the

direction of rudder?

(The given options represent top view of the boat)

!

A. B. C.

D. None of the given options

?

! A. Rabbit, Rhino

B. Giraffe, Wolf

C. Lion, Cheetah

D. Rabbit, Hawk

5. Now complete the following sequence Sun > Plants > ________ > Snake > ________

03Iken Scientifica 2011 | Question Set D

Food Chain

?

! A. Both I and II

B. II only

C. Both I and III

D. I only

6. Animals like lion prey on other animals such as deer, what will happen if there are no deer in the forest?

I. The lion would go to another area to hunt for food

II. The lion would eat barks and roots of trees

III. The lion population in the area will start dwindling.

?

! A. Another primary consumer like Zebra, which the lion can hunt

B. Some animal that hunts Lions

C. Another animal that hunts Deer

D. None of the above

7. Suppose a population of animal 'X' was introduced into the community. After the introduction of 'X', the

number of lions increased while the number of deer decreased. What do you think animal 'X' could be?

?

! A. I and IV

B. I, II and IV

C. I, II and III

D. II, III and IV

8. Over a period of time, the number of deer drops. Which of the following statements can explain it?

I. The producers are available in lesser number

II. More species of primary consumers exist

III. An increase in the lion population

IV. The death rate of the deer is lower than its birth rate

Rudder at theback of the boat

? 3. They have successfully crossed the bridge. Now they have to cross the main flooding river. The river is very deep

and totally flooded so building a bridge is not possible. They have 7 pieces of wooden logs with them and want

to create a raft using these logs to cross the river safely. Help them choose the best design from the following

options?

You cannot cut the logs. All the logs are of the same length and the logs are not very strong individually.

!

A. B. C. D.

Following is a case study. Answer the questions 5 to 8 based on information given below