English Medium कक्षा १० - CBSE Important Questions for Science

What is pollination?

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

Draw the well-labelled diagram of the human excretory system

Write Joule's law of heating.

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.

A student added few pieces of aluminium metal to two test tubes A and B containing aqueous solutions of iron sulphate and copper sulphate. In the second part of her experiment, she added iron metal to another test tubes C and D containing aqueous solutions of aluminium sulphate and copper sulphate.

In which test tube or test tubes will she observe colour change? On the basis of this experiment, state which one is the most reactive metal and why.

 Why are most carbon compounds poor conductors of electricity?

Mention any two components of blood.

Trace the movement of oxygenated blood in the body.

Write the function of valves present in between atria and ventricles.

Write one structural difference between the composition of arteries and veins.

Define excretion.

Name the basic filtration unit present in the kidney.

Name one gustatory receptor and one olfactory receptor present in human beings.

Write a and b in the given flow chart of the neuron through which information travels as an electrical impulse.

Name the hormones secreted by the given endocrine glands and specify one function.

Thyroid

Name the hormones secreted by the given endocrine glands and specify one function.

Pituitary

Name the hormones secreted by the given endocrine glands and specify one function.

Pancreas