To reduce exam fear, Class 7 Basic Science Question Paper Kerala Syllabus Set 3 provide good practice.
Kerala Syllabus 7th Standard Basic Science Model Question Paper Set 3
Time: 2¼ hour
Instructions:
- 15 minutes cool-off time is allotted for reading and understanding the activities.
- Answer any six questions.
Question 1.
a) Examine the statements given below. Classify them on the basis of the properties of acids and bases.
A. Has a sour taste
B. Turns pink when phenolphthalein is added
C. Slippery
D. Turns pink when methyl orange is added
E. Turns the colour of Pathimugam water into yellow
F. Red litmus turns blue
G. Reacts with metals to produce hydrogen
H. Has an alkaline taste
Answer:
| Properties of Acids | Properties of bases |
| Has a sour taste | Turns pink when phenolphthalein is added. |
| Turn the colour of the pathimugam water into yellow | Slippery |
| React with metal to produce hydrogen. | Red litmus turns blue |
| Has an alkaline taste |
b) Some acids and their uses are listed below. Find out the correct groups from them.
A. Acetic acid is used as a preservative and flavouring agent
B. Curd contains ascorbic acid. Used to make a drink
C. Sulphuric acid is used to make drinks
D. Nitric acid is used to make chemical fertilisers, paints and dyes
1. A and D are correct
2. C and D are correct
3. A and B are correct
4. All are correct
Answer:
1. A and D are correct
c) Among the liquids in the three beakers (A, B, C) placed on the table are an acid, a base and water. Suggest a method to identify them without tasting or smelling?
Answer:
Water: Neutral litmus paper will show no colour change.
Acid: Red litmus paper will stay red, but blue litmus paper will turn red.
Base: Blue litmus paper will stay blue, but red litmus paper will turn blue.
Question 2 has two parts 2 (A) and 2(B). Write any one 2(A) or 2(B) completely.
Question 2.
(A) a) Which method of purification can be adopted to separate freshwater from seawater?
a) Sifting
b) Chlorination
c) Distillation
d) Sedimentation
Answer:
c) Distillation
b) How do water bodies get polluted?
Answer:
- Disposal of plastic waste
- Spillage of a chemical substance
- Sewage from home, including human waste.
- Factory releases harmful chemicals and toxic substances directly into the river and lakes
c) What measures can we adopt to make water sources free from pollution ?
Answer:
Reducing waste, recycling materials, and reusing products can help to minimise the amount of waste. Encourage the use of organic fertilisers and natural pest control methods.
OR
(B) a) Examine the table given below and rewrite the mistakes, if any
| Organism | Parts that help in respiration |
| Earthworm | Gills |
| Fish | Moist skin |
| Frog | Book lungs |
| Spider | Lungs |
Answer:
| Organism | Parts that help in respiration |
| Earthworm | Moist skin |
| Fish | Gills |
| Frog | Lungs |
| Spider | Book lungs |
b) Observe the figure
The digestive systems of these animals share similarities with our own digestive system. What is your response to this statement?
Answer:
Yes. Like the digestive system of human beings, these animals have a mouth, oesophagus, stomach, small intestine, large intestine, rectum, etc.
c) Which among the following is correct in the group of omnivores?
A. Crow, Hen, Peacock
B. Man, Monkey, Peacock
C. Lion, Tiger, Deer
D. Goat, Elephant, Rabbit
1. A and B are correct
2. C and B are correct
3. C and D are correct
4. All are correct
Answer:
1. A and B are correct
Question 3.
Consider the following situations in everyday life:
- Tightly bound electric wires get sagged in summer.
- One end of a PVC pipe is heated, and the end of another pipe of the same diameter is inserted into it to join them.
a) Which of the following phenomena is responsible for the above situations?
A. Evaporation
B. Thermal Expansion
C. Condensation
D. Sublimation
Answer:
B. Thermal expansion
b) Hot tea of the same quantity is kept in an open steel tumbler and in a closed glass tumbler of the same size. Tea in which tumbler stays hot longer? Explain your findings on the basis of heat transmission.
Answer:
The tea in the closed glass tumbler stays hot longer than in the open steel tumbler. Because in an open tumbler, heat is lost quickly through convection and evaporation, cooling the tea. However, in a closed tumbler, the lid retains heat and steam, thereby reducing heat loss.
c) Observe the picture given below. What are the ways in which heat is transferred in the numbered positions?
Answer:
1 – Convection
2 – Conduction
3 – Radiation
Question 4.
a) Look at the statements below.
Statement I : The stamens of a flower in which artificial pollination is to be done are removed. Statement II: The stamens of the flower are removed to prevent self-pollination.
A. Statement I is true, and Statement II is not the correct reason.
B. Statement I is true, and Statement II is false. #
C. Statement I is false, and Statement II is wrong.
D. Statement I is true, and Statement II is the correct reason.
Answer:
D. Statement I is true, and Statement II is the correct reason.
b) Complete in the missing stages of artificial pollination.
Answer:
Stage 1: To prevent self-pollination, remove the stamen from the flower in which artificial pollination is to be done.
Stage 3: Pollen grains from the flower of a plant belonging to the same species but having different qualities are collected by using a brush.
c) Find the correct pair from the following.
A. Apiculture – Rearing Fish
B. Cuniculture – Rearing Rabbits
C. Floriculture – Rearing Honeybee
D. Pisciculture – Growing flowers
Answer:
B. Cuniculture -Rearing Rabbits
Question 5.
a) Examine the table and find out the correct group.
| 1) Hen | A) 4 Chamber |
| 2) Frog | B) 13 Chamber |
| 3) Fish | C) 2 Chamber |
| 4) Cockroach | D) 3 Chamber |
A. 1-A, 2-D, 3-C, 4-B
B. 1 -A, 2-C, 3-D,4-B
C. 1 -B, 2-D, 3-C, 4-A
D. 1 -C, 2-D, 3-A, 4-B
Answer:
A) 1-A, 2-D, 3-C, 4-B
b) Whose opinion do you agree with? Why?
Answer:
I agree with the opinion of the Manu, Because Arteries are the blood vessels that carry oxygen-rich blood from the heart to different body parts.
c) For maintaining the health of the heart, we have to follow some healthy habits. Write any two of them?
Name the device used to check the heartbeat?
Answer:
- Do Regular exercise
- Eat healthy food
Question 6 has two parts 6 (A) and 6 (B). Write any one 6 (A) or 6(B) completely.
Question 6.
(A) a) Observe the picture.
a) Which one shows the starting position of the lunar eclipse?
a) B
b) C
c) D
d) E
Answer:
a) B
b) Some statements are given below. Find out the correct group from them.
A. A Full Moon is the day when the part of the Moon on which the sunlight falls is completely visible from the Earth.
B. The waxing crescent Moon is visible overhead at sunset.
C. Solar eclipse occurs only on New Moon Day.
D. A lunar eclipse occurs on all Full Moon days.
1. A and C are correct
2. A and D are correct
3. C and D are correct
4. All are correct
Answer:
2. A and D are correct
c) Why is the spherical Moon seen in different shapes on different days?
Answer:
The Moon appears in different shapes throughout the month because of its orbit around the Earth. As the .Moon orbits, the amount of its illuminated surface that we can see from Earth changes.
Or
(B) The picture below shows a sample of honey.
a) Write an experiment to identify the pure honey.
Answer:
Materials required: Glass, Water, Honey
Procedure: Pure honey is poured into water.
Observation:
- Honey settles down
- Honey dissolves in water
Inference:
- If honey settles down. It is not adulterated
- If the honey is adulterated, it immediately dissolves in water.
b) What is adulteration?
Answer:
Adulteration means making a good product worse by adding cheap or harmful substances to it, or by taking away something valuable, usually to make more money.
c) What are the health risks associated with consuming adulterated food?
Answer:
Adulterated food can cause various health problems, such as allergies, digestive issues and even long-term health complications.