How many pairs of chromosomes are present in human beings ? Out of these how many are sex chromosomes ? How many types of sex chromosomes are found in human beings ? The sex of a new born child is a matter of chance and none of the parents may be newborn to justify this statement.

What type of questions asked from the lesson of magnetic effect of electric current 

Wavelength of green light is

A) 400-450 nm

B) 500-550 nm

C) 660-720 nm

D) 720-800 nm

What is the difference between anaerobic & aerobic respiration? Name some organism that uses the aerobic mode of respiration?

What are the main components of our environment? Explain each of them briefly.

What are examples of hydrotropism plants?