CBSE Class 8 Science The Invisible Living World: Beyond Our Naked Eye (Class 8 NCERT New) Quiz 6

1. What causes this growth on the fruit?

A Microorganisms (microbes) cause the powdery or cotton-like growth on the fruit. B Sunlight causes the powdery or cotton-like growth on the fruit. C Wind causes the powdery or cotton-like growth on the fruit. D Water droplets cause the powdery or cotton-like growth on the fruit.

2. But why do microorganisms not infect the pickles and murabbas?

A Because you add many spices with salt or sugar to them, which act as preservatives. High concentration of salt or sugar does not allow these organisms to grow on them. B Because pickles and murabbas are always kept in the refrigerator. C Because microorganisms cannot survive in glass jars. D Because pickles and murabbas are made only in winter.

3. The diversity of microorganisms plays a role in our daily life and helps clean the environment by:A. Breaking down waste and pollutantsB. Producing harmful toxinsC. Causing diseases onlyD. Preventing plant growth

A Breaking down waste and pollutants B Producing harmful toxins C Causing diseases only D Preventing plant growth

4. The purpose of this activity is:

A To understand the objective of the activity B To learn about historical events C To practice mathematical calculations D To explore scientific concepts

5. After 2–3 weeks, observe the changes that have taken place. Do you observe any difference in the contents of the container? Explain your observation.

A Yes, the contents of the container have decomposed and changed in appearance. B No, the contents of the container remain exactly the same as before. C The contents of the container have multiplied in quantity. D The contents of the container have turned into a liquid.

6. Manure is ______ and it helps the soil by ______.

A a natural fertilizer; improving its fertility B a type of pesticide; killing insects C a synthetic chemical; polluting the soil D a mineral; making soil harder

7. Peels of fruits and vegetables turn into manure by which process?

A By decomposition by microorganisms B By freezing them C By drying them in sunlight D By mixing them with chemicals

8. Gardeners collect dry leaves and plant waste and put them into pits because:

A they want to make compost for enriching the soil. B they want to keep the garden clean only. C they want to burn the waste later. D they want to attract insects.

9. The word 'Krimi' in ancient Indian texts refers to:

A A type of disease-causing organism B A sacred ritual C An ancient weapon D A form of traditional music

10. Fill in the blank: The process by which microorganisms break down complex substances of fallen leaves into simpler substances that are rich in nutrients is called ________.

A decomposition B photosynthesis C evaporation D condensation