To reduce exam fear, Class 7 Basic Science Question Paper Kerala Syllabus Set 1 provide good practice.
Kerala Syllabus 7th Standard Basic Science Model Question Paper Set 1
Time: 2¼ hour
Instructions:
- 15 minutes cool-off time is allotted for reading and understanding the activities.
- Answer any six questions.
Question 1.
a) You may have noticed that fans and tubelights are working in the classrooms when there are no students. Prepare a poster that includes instructions to prevent electricity waste,
Answer:
b) Observe the figure and explain how electricity is generated in hydroelectric power stations.
Answer:
Generators in hydroelectric power stations work using the energy obtained when water stored in reservoirs of dams falls from a height. In dams, water, which is stored in reservoirs, is carried through pipes and made to fall forcefully onto the turbines connected to the generators. The force of falling water rotates the turbines. The generators connected to the turbines start to work and produce electricity. This electricity is transmitted to various places through electric lines.
c) Which one of the following systems convert energy from the sun to electric energy?
A. Solar cells
B. Wind farm
C. Generator
D. Electric cell
Answer:
A. Solar cells
Question 2.
a) Examine the table and find out the correct group.
| 1. Urea | A.Biological control |
| 2. Tobacco decoction | B Chemical fertiliser |
| 3. Vermi compost | C.Organic pesticide |
| 4. Trichogramma | D.Organic fertiliser |
A) 1-B, 2-C, 3-D, 4-A
B) 1-A, 2-D, 3-C, 4-D
C) 1-D, 2-A. 3-B, 4-C
D) 1-A, 2-B, 3-C, 4-D
Answer:
A. 1-B, 2-C, 3-D, 4- A
(b) Whose opinion do you agree with? Why?
Answer:
I agree with the third Farmer. Organic and chemical fertilisers have their own merits and demerits. Farmers in our state employ a mixed method, applying a greater quantity of organic fertilisers and a lesser quantity of chemical fertilisers. Farmers also use microbial fertilisers for better yield.
c) Which method of pest control is by using traps or by hand picking? Name an equipment available in the market for this
Answer:
Mechanical control. Pheromone trap.
3. Question 3 has two parts 3(A) and 3(B). Write any one 3(A) or 3(B) completely.
Question 3.
(A) a) At which place is a land breeze and sea breeze felt strongly?
A. High Land
B. Mid Land
C. Coastal areas
D. Coastal areas and highland
Answer:
C. Coastal areas
b) Wind blows from sea to land during the day. What is the reason for this?
Answer:
During the day, the land gets heated up more quickly than the sea. The air above the land gets heated and expands. The air with lower density rises up. The comparatively cooler air above the sea blows towards the land. This is called sea breeze.
c) Statements regarding sea breeze and land breeze are given below. Among them select the right ones and classify them.
- At night breeze blow from sea to land.
- At daytime breeze flow from sea to land.
- At night sea gets cooled fast.
- At night breeze blow from land to sea.
- At night land gets cooled fast.
- At daytime the air above the land rises upwards.
- At daytime the air above the sea rises upwards.
Answer:
The integrated farming of crop cultivation and animal husbandry increases their income. By integrating methods, they can avoid sector-specific expenses, save space, and generate revenue from any field, at any time.
OR
(B) The data collected by visiting the fields of two farmers practising integrated farming is given below.
a) Which farmer interrelatedly utilises the resources to the maximum?
Answer:
Farmer-1
b) Justify your opinion.
Answer:
The integrated farming of crop cultivation and aninlal husbandry increases their income. By integrating methods, they can avoid sector-specific expenses, save space, and generate revenue from any field, at any time.
c) Give two suggestions to the farmers who practice integrated farming.
Answer:
Use cow dung for paddy fields as an organic manure. The straw obtained from paddy cultivation, the bran obtained from husking paddy grains, etc can be given to cattle as fodder, and the organic wastes from homes and agricultural fields can be utilized towards the gas plant.
Question 4.
Some observations related to acids and alkalis are given below.
Solution – 1
No change in colour while adding Phenolphthalein. The colour changed into pale pink while adding Methyl orange. The colour did not change when the solution was added to the cloth rubbed with turmeric.
Solution – 2
Formed pink colour while adding Phenolphthalein. Formed pale yellow colour on adding Methyl orange. Formed red colour when the solution was added to the cloth rubbed with turmeric.
a) List out the chemical properties of solution 1 & solution 2 in the given table
| Solution | Chemical Properties |
| Solution – 1 | |
| Solution – 2 |
Answer:
| Solution | Chemical properties |
| Solution -1 |
|
| Solution -2 |
|
b) Write down any two general properties of solution 2.
Answer:
- Slippery or Soapy Feel.
- Turns Red Litmus Paper Blue
c) Find out the right pair from the following.
1. Automobile battery: hydrochloric acid
2. Manufacturing of soap: caustic soda
3. Preparation of pickle: sulphuric acid
4. Manufacture of paint: caustic soda
Answer:
2. Manufacturing of soap: caustic soda
Question 5.
Observe the picture.
a) Which among the following can be used to light the bulb in the above arrangement? Why?
[Copper wire. Glass, Aluminium wire, Refill, Iron wire, Rolled paper, Pencil graphite]
Answer:
Copper wire. Aluminium wire, Iron wire. Pencil graphite. All these are good conductors of electricity
b) The symbols used in circuit diagrams are given below. Name them.
Answer:
a-Cell,
(b is already given)
c-Wire
c) Draw the symbols of switch ‘on’ and ‘off’ positions.
Answer:
6. Question 6 has two parts 6 (A) and 6 (B). Write any one 6 (A) or 6(B) completely.
Question 6.
(A) The following are the peculiarities of two types of guava.
| Variety A | High resistance to diseases | Fruits are less sweet | Fruits are small in size |
| Variety B | Low resistance to diseases | Fruits are more sweet | Fruits are big in size |
a) Write the peculiarities of the saplings produced by the hybridization of these two varieties.
| Sapling 1 | Low resistance to disease, less sweet, big in size |
| Sapling 2 | |
| Sapling 3 | |
| Sapling 4 | |
| Sapling 5 |
Answer:
Sapling – 2 – High resistance, fruits are more sweet, fruits are small in size.
Sapling – 3 – Low resistance to disease, Fruits are less sweet, Fruits are small in size.
Sapling – 4 – High resistance to disease, Fruits are less sweet, Fruits are big in size.
Sapling – 5 – Low resistance to disease, Fruits are more sweet, Fruits are big.
b) Write the peculiarities of hybrid plants which have the most desirable qualities of these two varieties.
Answer:
High and Quick yield. Resistance to infections.
c) Write the names of any two hybrid paddy seeds.
Answer:
Pavitra, Annapurna, Hraswa
OR
(B) a) Examine the situations given below.
i. Changing bulb when the switch is on
ii. Using footwear while ironing clothes.
iii. Turning on the switch with wet hand
iv. Changing bulb when the switch is off Identify the situations that may cause electric shock.
A. i and ii
B. ii and iii
C. i and iii
D. ii and iv
Answer:
C. i and iii
b) A broken electric line is lying on the mango tree by the road side. Write a safety measure that you would take in this situation and the reason for it.
Answer:
In the event of a broken electric line, the most important safety measure is to stay away from the area and immediately report it to the local electricity board or emergency services. This is because the ground and the surrounding objects could be energised, creating a severe risk of electrocution.
c) Write any two initial steps to be taken to rescue a person experiencing an electric shock.
Answer:
The first thing to be done is to disconnect the electrical contact. You can switch off or remove the fuse for this. If it is not possible, separate the person from the electric circuit using a dry wooden stick or some other good insulator.
- In the case of heart failure, perform chest compressions. Place one hand on top of the other and apply continuous pressure on the victim’s chest. This should be done tintil the heart starts beating again.
- If breathing stops, give artificial respiration. Keep the body warm by massaging.
- Take the person immediately to a hospital if the shock is severe.