Important Questions for CBSE (English Medium) Class 10 - CBSE - Science

Write the functions of the following parts in human female reproductive system:-

(i) Ovary

(ii) Oviduct

(iii) Uterus

Describe the function of placenta.

List three distinguishing features, in tabular form, between acquired traits and the inherited traits.

Write the function of the following part of the human eye: Cornea

Write the function of the following part of the human eye: crystalline lens

Write the function of the following part of the human eye: ciliary muscles

Draw the well-labelled diagram of the human excretory system

What is atmospheric refraction? Use this phenomenon to explain the following natural events:

Twinkling of stars

Draw diagrams to illustrate your answers.

List any four methods of contraception used by humans. State in brief two advantages of adopting such preventive methods.

Explain how the embryo gets nourishment inside the mother’s body.

A student in viewing under a microscope a permanent slide showing various stages of asexual reproduction by budding in yeast. Draw diagrams of what he observes (in proper sequence)

What is meant by a power of a lens? Define its SI unit. 

Principle of Electric motor

Decomposition reactions require energy either in the form of heat or light or electricity for breaking down the reactants. Write one equation each for decomposition reactions where energy is supplied in the form of heat, light and electricity

2 mL of sodium hydroxide solution is added to a few pieces of granulated zinc metal taken in a test tube. When the contents are warmed, a gas evolves which is bubbled through a soap solution before testing. Write the equation of the chemical reaction involved and the test to detect the gas. Name the gas which will be evolved when the same metal reacts with dilute solution of a strong acid.

What is observed when a solution of sodium sulphate is added to a solution of barium chloride taken in a test tube? Write equation for the chemical reaction involved and name the type of reaction in this case.

The pH of a salt used to make tasty and crispy pakoras is 14. Identify the salt and write a chemical equation for its formation. List its two uses.

 Why are most carbon compounds poor conductors of electricity?

Write the steps involved in the extraction of pure metals in the middle of the activity series from their carbonate ores.

How is copper extracted from its sulphide ore? Explain the various steps supported by chemical equations. Draw labelled diagram for the electrolytic refining of copper.