BASIC STRUCTURE OF A CELL
Every cell has three important structures . The nucleus, cytoplasm and cell membrane. THE NUCLEUS : The dark circular spot present inside the cell is called nucleus. It controks all the functions of cell hence it is called " control room of cell". It has genetic material either DNA or RNA which helps in passing the characters from parents to offsprings. The nucleus also plays a major role in cell division. The membrane covering the nucleus is caller nuclear membrane. The fluid present inside the nucleus is called nucleoplasm. Based on the presence or absence of nucleus ,the cells can be of two types: PROKARYOTIC CEL L: The cells which do not have membrane bound nucleus are called prokaryotic cells Such organisms are called prokaryotes . Ex: Bacteria, cyanobacteria , blue green algae etc. EUKARYOTIC CELLS: The cells which has membrane bound nucleus are called eukaryotic cells . Such organisms are called eukaryotes . Ex: All higher plants and animals. Few exceptions are RBC&