Cellular structures are necessary for everyday cycle. I will selected two cellular structures.
(1) Chloroplast: The most important function of the chloroplasts is to carry out the process of photosynthesis. The process of photosynthesis includes light reaction and dark reaction. If chloroplasts is damaged then photosynthesis will not be taken place.
(2) Nucleus: The nucleus can be called "controlling centre of the cell" since it contains chromosomes and genes, which control all activities of an individual cell. If nucleus is damaged, cell would die. Chromosomes which are present within the nucleus are responsible for deciding whether a fertilized egg will develop into a cow, a mango tree or into a man.