Conservation of plants and animals — Science STD 8 — Question

Name two animals which undergo metamorphosis and two which do not.

Name the gas present in atmosphere which is mainly responsible for causing global warming.

Name a device which works on the reflection of reflected light.

The incomplete combustion of firewood in homes produces a very poisonous gas X. When inhaled, gas X combines with the substance Y present in blood and reduces the capacity of blood to carry gas Z causing respiratory problems and suffocation. What are X, Y and Z?

What do you understand by the term 'point of incidence'?

Explain why, it might be dangerous to raise an umbrella over our head in a thunderstorm.

Name the instrument used to measure and record an earthquake.

In the context of an earthquake, which one is deep under the ground: focus or epicentre?

What is a meteor? What is the other name of a meteor?

Why do brake pads of bicycles have to be replaced quite often?