Which of the following can be made into crystal?

$(a)$ What is $DNA$? Where is it found?
$(b)$ Name the functional segment of $DNA$.

Chromosomes are made up of

We eat food composed of all the nutrients like carbohydrates,proteins,fats,vitamins,minerals,and water. After digestion,these are absorbed in the form of glucose,amino acids,fatty acids,glycerol,etc. What mechanisms are involved in the absorption of digested food and water?

Identify the type of cell and write one characteristic feature for each of the following descriptions:
$(i)$ Large vacuole,nucleus pushed to the periphery.
$(ii)$ Cell does not burst even in a very dilute medium.
$(iii)$ Nuclear region is not well-defined and is known as the nucleoid.

Name the processes by which $CO_{2}$ and $H_{2}O$ move into and out of the cell.