Self Assessment Model Paper – 2 (2025-26)
Class : 8 | Subject : Biological Science
Section A
1. Identify the crop which grows in kharif season.
A) wheat
B) ground nut
C) mustard
D) linseed
Answer: B) ground nut
2. Which of the following statements is true about manures?
A) It decreases water holding capacity.
B) It makes soil impervious to water.
C) It decreases friendly microbes.
D) It improves soil texture.
Answer: D) It improves soil texture
3. Identify the modern methods of irrigation
1 - moat
2 - drip
3 - rahat
4 - sprinkler
A) 1 and 2 only
B) 2 and 3 only
C) 1 and 3 only
D) 2 and 4 only
Answer: D) 2 and 4 only
4. What is the use of the instrument given in the picture?
A) harvesting
B) Leveling
C) seed drilling
D) ploughing
Answer: A) harvesting
5. Ravi is growing wheat in his field. He notices that unwanted plants are growing along with the crop and competing for nutrients. What should he do to solve this problem?
A) Add more fertilizers so that both weeds and crops can grow.
B) Water the field more frequently to reduce competition.
C) Remove the weeds, since they compete with the crop for resources.
D) Allow the weeds to grow, as they protect the soil from erosion.
Answer: C) Remove the weeds
6. Identify the correct match:
A) Hoe – levelling
B) Rabi crop – cotton
C) chain pump – modern irrigation method
D) Holi, Diwali – harvest festivals
Answer: C) chain pump – modern irrigation method
7. Identify the suitable titles for Group A and Group B respectively.
A) sowing seeds, storage of grains
B) irrigation methods, weeding methods
C) harvesting methods, modern irrigation methods
D) agricultural practices, fertilizers
Answer: D) agricultural practices, fertilizers
8. Choose the correct answer based on the given assertion and reason
Assertion (A): Spraying of weedicides may not affect the health of farmer.
Reason (R): The farmers should cover their nose and mouth with a piece of cloth while spraying chemicals.
A) A is true but R is false
B) A is false but R is true
C) Both A and R are true. R is the correct explanation of A
D) Both A and R are true. R is not the correct explanation of A
Answer: B) A is false but R is true
9. In which pot plants grow faster?
A) A
B) B
C) C
D) D
Answer: B
10. A farmer wants to increase his crop production. Which practice should he follow before sowing?
A) Select clean, healthy, high-yielding seeds.
B) Sow all seeds very close together.
C) Avoid adding manure before sowing.
D) Select less expensive seeds.
Answer: A) Select clean, healthy, high-yielding seeds
11. Four students made the following statements about farm implements. Whose statement is correct?
A) Vennela
B) Suhana
C) Rajesh
D) Praveen
Answer: C) Rajesh
12. A scientist invented an instrument that can supply water to plant drop by drop directly near the roots. Which types of crops can be benefitted by this type of irrigation method?
A) lawns
B) Coffee plantations
C) fruit plants
D) Paddy crop
Answer: B) Coffee plantations
13. Identify the bacteria lives in root nodules of Leguminous plants roots.
A) Rhizobium
B) Rhizopus
C) Plasmodium
D) Lactobacillus
Answer: A) Rhizobium
14. Which of the following statements best describe the animal husbandry?
A) Catching fish from rivers
B) Growing fishes in paddy fields
C) Providing proper food, shelter and care to farm animals in large scale
D) Storing milk products and grain
Answer: C
15. A farmer stores freshly harvested grains in damp jute bags without drying them properly. After some time, the grains get spoiled. What is the most logical reason?
A) The grains absorbed moisture, allowing fungi and insects to multiply.
B) The jute bags reacted with the grains.
C) The grains lost nutrients.
D) The grains became hard due to lack of air.
Answer: A
Section B
16. Write any two uses of ploughing.
Answer:
-
It helps in easy penetration of roots.
-
It increases water holding capacity of the soil.
-
It promotes growth of useful microorganisms.
-
It improves soil fertility.
(Any two)
17. What are weeds? How do weeds damage crops?
Answer:
Weeds are the undesirable plants that grow along with crop plants.
They damage crops by:
-
Competing for water, nutrients, space and sunlight.
-
Reducing crop yield.
Section C
18. Write down the procedure you followed in your school laboratory to separate good quality seeds from bad quality seeds.
Answer:
Materials: Beaker, water, green gram seeds
Procedure:
-
Take a beaker and fill half of it with water.
-
Put a handful of seeds in the water and stir.
-
Wait for some time.
Observation:
Some seeds float and some sink.
Explanation:
Floating seeds are damaged seeds.
Sinking seeds are healthy seeds.
Conclusion:
Good quality seeds can be separated from bad seeds by this method.
19. Fill the following chart.
Preparation of soil → Sowing → Manuring → Irrigation → Harvesting
Protecting from weeds → Harvesting → Storage
Section D
20. A) How can you differentiate fertilizers from manures?
Fertilizers
-
Man-made inorganic substances.
-
Prepared in factories.
-
Rich in nutrients like nitrogen, phosphorus and potassium.
-
Provide nutrients quickly.
Manures
-
Natural substances formed from decomposition of plant and animal waste.
-
Prepared in fields.
-
Improve soil fertility and humus content.
-
Less rich in nutrients.
OR
B) Explain how continuous planting of the same crop affects soil and suggest solutions.
Effects
-
Soil becomes poor in nutrients.
-
Soil fertility decreases.
Solutions
-
Add manure or fertilizers to replenish nutrients.
-
Practice crop rotation.