The method of incorporating desirable characters into crop varieties is by

Animal feed includes vitamins and proteins mainly.

Define the terms hybridization and photoperiod.

Animal husbandry is the scientific management of
$(i)$ animal breeding
$(ii)$ culture of animals
$(iii)$ animal livestock
$(iv)$ rearing of animals

Nakul was shooting his arrows towards a target. Every time the arrow fell short of the target. This annoyed him. His brother, Arjun, came to his rescue. He showed his brother the right way to shoot an arrow. When Nakul tried again, he found that the arrows started hitting the target.
$(a)$ What do you think Arjun might have told Nakul?
$(b)$ What are the values imbibed by Arjun?

Dalton was the first scientist to use symbols for elements. Chemical symbols act as a vocabulary of chemical language. Chemical symbols are used to describe chemical changes with clarity and precision. Chemical symbols help in identifying specific elements. Chemical symbols also represent an atom of a particular element. Chemical symbols also signify the atomic mass of an element.
$(a)$ How do symbols help in identifying specific elements?
$(b)$ How do we use symbols in daily life for our convenience?
$(c)$ What values do you find in using symbols?