Secondary School (English Medium) (5 to 8) Class 8 - CBSE Question Bank Solutions for Science

Unscramble the underlined word in the following sentence.

Dannalier helps the body to adjust and fight the stress.

Complete the following sentence.

In females, the uterine wall thickens to receive the ______.

Complete the following sentence.

Release of sex hormones is under the control of a hormone secreted from the ______.

Give a suitable word for the following statement.

The site which responds to a hormone.

Give a suitable word for the following statement.

Chemicals which control changes at adolescence stage.

Name the female hormone produced by ovaries that helps in development of mammary glands.

Match the hormones given in Column A with their deficiency disease given in Column B.

Name the hormone which would be released during the following situations:

1. A frightened person.
2. Growth of a child to adult.
3. Development of caterpillar to moth.
4. Development of tadpole to frog.

In human females, each time during maturation and release of egg the inner wall of uterus thickens. Is this thickening permanent? Give reasons.

A toy car released with the same initial speed will travel farthest on

Which of the following statements is incorrect?

In a large commercial complex there are four ways to reach the main road. One of the path has loose soil, the second is laid with polished marble, the third is laid with bricks and the fourth has gravel surface. It is raining heavily and Paheli wishes to reach the main road. The path on which she is least likely to slip is ______.

Imagine that an object is falling through a long straight glass tube held vertical, air has been removed completely from the tube. The object does not touch the walls of the tube. Will the object experience any force of friction?

Is there a force of friction between the wheels of a moving train and iron rails? If yes, name the type of friction. If an air cushion can be introduced between the wheel and the rail, what effect will it have on the friction?

An electric current can produce

Boojho and Paheli performed experiments taking similar bulbs and cells but two different solutions A and B as shown in the following figure.

Boojho's Experiment	Paheli's Experiment
(A)	(B)

They found that the bulb in the setup A glows more brightly as compared to that of the setup B. You would conclude that

Boojho’s uncle has set up an electroplating factory near his village. He should dispose off the waste of the factory

When electric current is passed through a conducting solution, there is a change of colour of the solution. This indicates

Which of the following metals is used in electroplating to make objects appear shining?

The object to be electroplated is taken as ______ electrode.