The nucleus is a part of cells which is easily seen. It is very important because it controls all the activities of the other parts that occur within the cell. The nucleus contains materials that play a role in heredity. The plasma membrane encloses the cell and separates what is inside it from its environment. It also controls what goes into and out of the cell. The plasma membrane allows entry of materials needed by the cell and eliminates those which are not needed. The cytoplasm consists of a jelly-like substance where all the other parts of the cell are located. It does not however, include the area where the nucleus is located. Many different activities of the cell occur in the cytoplasm. The cell wall is made of stiff material that forms the outermost part of plant cells. This gives shape and protection to them. The Golgi body packages proteins inside the cell before they are sent to their destination. It is particularly important in the processing of proteins for secretion. Chloroplasts are responsible for conducting photosynthesis in plants. They also carry out almost all fatty acid synthesis in plants, and are involved in the immune response of plants. The mitochondrion generates most of the cell’s supply of ATP used as a source of chemical energy in plants. They also control the cell cycle and cell growth of the plant. Lysosomes are cellular organelles that contain acid hydrolase enzymes that break down waste materials and cellular debris. They can dispose extra compounds in the cell and can digest them too. Ribosomes serve as the primary site of biological protein synthesis. They link amino acids together in the order specified by messenger RNA molecules. The endoplasmic reticulum is an organelle of cells in eukaryotic organisms that form an interconnected network of membrane vesicles. A vacuole is an enclosed compartment which is filled with water containing inorganic and organic molecules. They remove the harmful materials that may give threat to the cell. Centrioles are only present in animal cells. It is mainly composed of tubulins that are only present in animals. They are responsible for animal reproduction.