CBSE Class 9 Science Assertion Reason MCQs
CBSE Class 9 Science – Assertion & Reason MCQs
Class: 9 | Subject: Science | Section: Exam Oriented
Topic: Assertion Reason MCQs – CBSE Board Examination Pattern
Topic: Assertion Reason MCQs – CBSE Board Examination Pattern
Instructions: These Multiple Choice Questions (MCQs) are designed strictly as per the NCERT syllabus, making them ideal for CBSE Class 9 Science examinations. Each question follows the Assertion–Reason format to strengthen conceptual clarity.
1. Assertion: All living organisms are made of cells.
Reason: Cells arise from pre-existing cells.
Reason: Cells arise from pre-existing cells.
Answer: B
Assertion is Cell Theory. Reason is also correct but explains cell origin, not that organisms are made of cells.
Assertion is Cell Theory. Reason is also correct but explains cell origin, not that organisms are made of cells.
2. Assertion: Mitochondria are called the powerhouse of the cell.
Reason: They store genetic material.
Reason: They store genetic material.
Answer: C
Mitochondria produce ATP energy. Genetic material storage is the nucleus function.
Mitochondria produce ATP energy. Genetic material storage is the nucleus function.
3. Assertion: Diffusion occurs faster in gases.
Reason: Gas particles have high kinetic energy.
Reason: Gas particles have high kinetic energy.
Answer: A
High kinetic energy increases particle movement, speeding diffusion.
High kinetic energy increases particle movement, speeding diffusion.
4. Assertion: Sound cannot travel in vacuum.
Reason: Sound waves require a material medium.
Reason: Sound waves require a material medium.
Answer: A
Sound is a mechanical wave and needs particles to propagate.
Sound is a mechanical wave and needs particles to propagate.
5. Assertion: Plastids are absent in animal cells.
Reason: Animals do not perform photosynthesis.
Reason: Animals do not perform photosynthesis.
Answer: A
Plastids like chloroplasts perform photosynthesis, absent in animals.
Plastids like chloroplasts perform photosynthesis, absent in animals.
6. Assertion: Density of a substance is constant.
Reason: It depends on mass and volume ratio.
Reason: It depends on mass and volume ratio.
Answer: A
Density = Mass/Volume. For a pure substance this ratio remains constant.
Density = Mass/Volume. For a pure substance this ratio remains constant.
7. Assertion: Velocity is a vector quantity.
Reason: It has magnitude and direction.
Reason: It has magnitude and direction.
Answer: A
Vector quantities require both magnitude and direction.
Vector quantities require both magnitude and direction.
8. Assertion: Boiling is a bulk phenomenon.
Reason: It occurs at all temperatures.
Reason: It occurs at all temperatures.
Answer: C
Boiling is bulk but occurs only at boiling point.
Boiling is bulk but occurs only at boiling point.
9. Assertion: Ozone protects Earth.
Reason: It absorbs UV radiation.
Reason: It absorbs UV radiation.
Answer: A
UV absorption prevents harmful radiation reaching Earth.
UV absorption prevents harmful radiation reaching Earth.
10. Assertion: Force can change shape.
Reason: Force can change speed.
Reason: Force can change speed.
Answer: B
Both are effects of force but independent.
Both are effects of force but independent.
11. Assertion: Evaporation causes cooling.
Reason: High energy particles escape.
Reason: High energy particles escape.
Answer: A
12. Assertion: Plant cells have cell walls.
Reason: It provides rigidity.
Reason: It provides rigidity.
Answer: A
13. Assertion: Acceleration can be negative.
Reason: Velocity decreases.
Reason: Velocity decreases.
Answer: A
14. Assertion: Prokaryotes lack nucleus.
Reason: DNA is in nucleoid.
Reason: DNA is in nucleoid.
Answer: A
15. Assertion: Inertia depends on mass.
Reason: Heavier objects resist motion more.
Reason: Heavier objects resist motion more.
Answer: A
16. Assertion: Chlorophyll is green.
Reason: It reflects green light.
Reason: It reflects green light.
Answer: A
17. Assertion: Speed is scalar.
Reason: It lacks direction.
Reason: It lacks direction.
Answer: A
18. Assertion: Water is universal solvent.
Reason: It dissolves many substances.
Reason: It dissolves many substances.
Answer: A
19. Assertion: Metals conduct electricity.
Reason: They have free electrons.
Reason: They have free electrons.
Answer: A
20. Assertion: Air exerts pressure.
Reason: Air has weight.
Reason: Air has weight.
Answer: A