Lysosomes arise from:

Who observed the cell for the first time and when?

$(i)$ Why is the cell called the structural and functional unit of life?
$(ii)$ Why is the plasma membrane called a selectively permeable membrane?
$(iii)$ Name the factor which decides the movement of water across the plasma membrane.

Name the plastid which stores starch,oils and protein granules.

What type of enzymes are present in the lysosomes? What is their function? Which cell organelles manufacture these enzymes?

Which of the following can be made into crystal?