Class 7 Science

Sample Paper – 4

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General Instructions:          

(1) All questions are compulsory.

(2) This question paper contains 23 questions divided into four Sections A, B, C and D.

(3) Section A comprises 3 Questions (Fill in the Blanks, Multiple choice questions and True and False) of 20 marks.

(4) Section B comprises 8 questions of 2 marks each.

(5) Section C comprises 8 questions of 3 marks each.

(6) Section D comprises 4 questions of 5 marks each.

 

SECTION – A

Question 1:

FILL IN THE BLANKS:                                                                       (1 x 10 = 10)

1. Amoeba digests its food in the ___________.

2. Clothes of __________ colours absorb more heat better than clothes of light colours.

3. The surface of water can act like a __________.

4. Lungs are present in the __________.

5. Substances that are used to indicate whether a substance is acid or a base are known as __________.

6. Longer line in the symbol for a cell represents its __________ terminal.

7. An image that cannot be obtained on a screen is called __________.

8. Phenolphthalein is an indicator giving a pink colour in case of __________ solution.

9. The decaying leaves and animal droppings in a forest enrich the __________.

10. Dried ___________ is used as manure.

 

Question 2:

Choose the correct answer:                                                                    (1 X 5 =5) 

1.The breakdown of complex components of food into simpler substances is called

(a) ingestion

(b) egestion

(c) assimilation

(d) digestion

 

2. The distance travelled by the vehicles is recorded by

(a) monometer

(b) odometer

(c) speedometer

(d) motometer

 

3.When breakdown of glucose occurs wwith the use of oxygen, it is called

(a) anaerobic respiration

(b) aerobic respiration

(c) regular respiration

(d) all of these

 

4. Which of the following protects the lining of the stomach?

(a) Digestive juices

(b) Mucous

(c) Hydrochloric acid

(d) None of the above

 

5. In the cells, which of the following gases helps in the breakdown of food after we breathe in air?

(a) Carbon dioxide

(b) Oxygen

(c) Nitrogen

(d) Hydrogen

 

Question 3:

Write ‘True’ or ‘False’:                                                                       (1 X 5 = 5)

1. The tongue helps in mixing food with saliva.

2. Tooth decay is caused by the presence of a base.

3. Condensation of steam is not a chemical change.

4. Frogs breathe through their skins as well as their lungs.

5. Decreased physical activity enhances the rate of breathing.

 

SECTION – B (2 Marks each)

Question 4:

Explain cellular respiration.

 

Question 5:

If the filament of Spirigyra is broken into fragments. What will you observe?

 

Question 6:

Write the characteristics of acids by which we can identify acids?

 

Question 7:

It is necessary to ban the use of polythene bags and plastics. Do you agree? If yes, why?

 

Question 8:

Urine is called an excretory product. Why?

 

Question 9:

If a pan is removed from the fire, then why does it cool down?

 

Question 10:

Why do we cover plug pinholes which are within the reach of children with cello tape or a plastic cover when not in use?

 

Question 11:

Why do muscle respire anaerobically during heavy exercise?

 

Section – C (3 marks each)

Question 12:

What is a salt? Name any salt and give their formulae.

 

Question 13:

(a) Name the only artery that carries carbon dioxide rich blood.

(b) Why is it called an artery if it does not carry oxygen-rich blood?

 

Question 14:

We need a shiny surface for reflection. Explain why.

 

Question 15:

“Forest is a dynamic entity, full of life and vitality”. Explain briefly.

 

Question 16:

Coconut is a large and heavy fruit. How is it adapted for dispersal by water?

 

Question 17:

Discuss the various associated glands of digestive system and their role in digestion.

 

Question 18:

The freezer is located at the top of the refrigerator. Explain why.

 

Question 19:

Describe onsite disposal systems.

 

Section – D (5 marks each)

Question 20:

Life would be impossible without plants. Explain, how.

                                                     OR

Plants are known as the producers of a food chain. Give reason.

 

Question 21:

How farmer is benefited from symbiotic relationship between Rhizobium bacteria and legumes?

 

Question 22:

Starting from A, Paheli moves along a rectangular path ABCD as shown in figure. She takes 2 min to travel each side. Plot a distance-time graph and explain whether the motion is uniform or non-uniform.

 

Question 23:

Explain the following.
(a) Copper and aluminium wires are usually employed for electricity transmission. Explain the reason.
(b) Explain how does the resistance of a wire vary with its length.
(c) The tungsten is used almost exclusively for filament of electric lamp. Comment.

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