Basically cytoplasm is the substance that fills the cell. It is a jelly-like substance and it is made up of eighty percent water and is usually clear and colorless. Cytoplasm is a thick gel-like substance. It liquefies when it is agitated or stirred. Cytoplasm is referred as cytosol, which means substance of the cell. This name describes it, the cytoplasm is the substance of life, the cytoplasm serves as a molecular soup, it is in the cytoplasm where all the cellular organelles are suspended and are bound together by a lipid bilayer membrane. The cell membrane surrounds the cytoplasm and it also surrounds the nucleus and the cellular organelles. The cytoskeleton present in the cytoplasm gives the cell its shape. The cytoplasm constitutes of dissolved nutrients and it aids to dissolve waste products.
The cell membrane or the cytoplasmic membrane or the plasma membrane is a biological membrane, it separates the cell interior from the external environment. The cytoplasmic membrane shows selective permeability to organic molecules and ions. It controls in and out movement of substances in the cells. The main function of the cell membrane is to protect the cell from its surrounding environment. The cell membrane is made of the phospholipid bilayer in which the proteins are embedded. The cell membrane performs various processes of the cells like ion conductivity, cell adhesion, and cell signaling. It also serves as attachment for certain cellular structures like the cell wall, glycocalyx and intracellular cytoskeleton.
Cytoplasm is the fluid where the cellular organelles are suspended. It fills up the spaces that are not occupied by the organelles. The constituents of cytoplasm are cytosol, organelles and cytoplasmic inclusions.
Cytosol: Cytosol makes up about 70% of the volume of the cell. It is composed of water, salts and organic molecules. Cytosol is composed of a mixture of cytoskeleton filaments, organic and inorganic molecules that are dissolved and water. It also contains protein filaments that make up the cytoskeleton, and also soluble proteins and structures like ribosomes, proteasomes are also present. The inner, more fluid and granular position of the cytoplasm is known as the endoplasm. The network of fibers and high concentrations of the dissolved macromolecules like proteins causes macromolecular crowding. This effect how the components of the cytoplasm interact with each other.
Organelles: Organelles mean "little organs", that are membrane bound. They are present inside the cell and perform specific functions that are necessary for the survival of the cell. Some of the constituents of the cell that are suspended in the cytosol are cellular organelles like mitochondria, endoplasmic reticulum, Golgi apparatus, vacuoles, lysosomes and chloroplasts in plant cells.
Cytoplasmic Inclusions: The cytoplasmic inclusions are tiny particles suspended in the cytosol. A vast range of inclusion is present in different cell types. The inclusions range from calcium oxalate crystals or silicon dioxide crystals in plants to storage granules of materials like starch, glycogen, etc. Lipid droplets are a widespread example of inclusions, these are spherical droplets, and they are made of lipids and proteins and are present in both prokaryotes and eukaryotes as a medium to store lipids like fatty acids and sterols. These droplets take up much of the volume of adipocytes which are specialized storage cells, they are also found in other types of cells also.