Protoplasm is the living material of a cell: everything inside the cell surface membrane. It is made of two parts:
• the nucleus, whose contents are called the nucleoplasm
• the cytoplasm, which is everything outside the nucleus but inside the cell surface membrane, including the organellesprotoplasm = nucleus + cytoplasm The cytoplasm itself consists of the organelles suspended in the cytosol, the fluid part. Cytosol is mostly water (about 70 to 90% of a cell's mass is water), containing dissolved ions, sugars, amino acids, ATP, nucleotides, enzymes and other proteins. It is not a simple liquid: the cytoskeleton runs through it, and it is often described as having a jelly-like consistency.Roles of the cytosol
• It is the site of many metabolic reactions, for example glycolysis, the first stage of respiration.
• Proteins that stay in the cytoplasm are made on free ribosomes here.
• Being mostly water, it is a solvent in which reactions happen and in which substances move by diffusion and cytoplasmic streaming.
• It stores materials, such as glycogen granules in liver and muscle cells.In plant cells the cell wall is non-living, so it is not part of the protoplasm. The protoplasm of a single plant cell, with its wall removed, is called a protoplast. The contents of the large vacuole (cell sap) are also usually treated as outside the living cytoplasm.
• the nucleus, whose contents are called the nucleoplasm
• the cytoplasm, which is everything outside the nucleus but inside the cell surface membrane, including the organelles
• It is the site of many metabolic reactions, for example glycolysis, the first stage of respiration.
• Proteins that stay in the cytoplasm are made on free ribosomes here.
• Being mostly water, it is a solvent in which reactions happen and in which substances move by diffusion and cytoplasmic streaming.
• It stores materials, such as glycogen granules in liver and muscle cells.In plant cells the cell wall is non-living, so it is not part of the protoplasm. The protoplasm of a single plant cell, with its wall removed, is called a protoplast. The contents of the large vacuole (cell sap) are also usually treated as outside the living cytoplasm.