Cytoplasm - Cytosol, Definition, Structure and Function

What is Cytoplasm?

 

The cytoplasm is jelly-like material (aqueous matrix ) filling the cell, which suspended all the cell organelles,  such as endoplasmic reticulum, mitochondria, ribosome, vacuoles, etc, enclosed within the cell membrane. 

The cytoplasm is responsible for giving its shape means helps keep the shape of the cell.

The cytoplasm consists of all of the contents outside of the nucleus and is enclosed within the plasma membrane or cell membrane of a cell. 

The substance inside the plasma membrane and external to the nucleus is called cytoplasm and the substance found within the cell nucleus, bounded by the nuclear membrane is called the nucleoplasm.

 

The cytoplasm consists of all the cellular content between the plasma membrane and nucleus has "two compartments".

 

1. Cytosol 

 

It is a watery substance and does not contain organelles.  The fluid portion of the cytoplasm contains 70-85% water, and dissolves solutes and suspended particles.

Cytosol serves as the site of biochemical reactions, where many chemical reactions take places such as anaerobic glycolysis and protein synthesis

 

2. Organelles (little organ)

 

Each type of organelles has a characteristic shape and specific reaction, that is membrane-bound.  Without cytoplasm, the cell would be deflated and material not be able to pass easily from one organelle to another.

 

Structure of Cytoplasm

 

 

 Functions of Cytoplasm

 

Key Functions include- 

1. It is a site for many biochemical reactions takes place for a cell's existence. 

 

2. Important function such as protein synthesis, glycolysis (breakdown of glucose), gluconeogenesis (generation of glucose from certain non-carbohydrate sources), and HMP or Pentose phosphate pathway (an alternative pathway to glycolysis, and intermediates for the synthesis of nucleotides) takes place in the cytosol.

 

3. It is a place where the cell expands, provides the building blocks for maintaining cell structure, and for the growth of the cell takes place.

 

4.  Organelles perform specific functions in cellular growth maintenance and maintaining homeostasis.

 

5. Cytoplasm keeps organelles in place. It is responsible for holding the components of the cell and protecting them from damage.

 

6.  It helps in maintain the shape of cells and cell movement.

 

7. Cytosol contact with cellular organelles. It helps in the exchange of material and acts as a vehicle for the transport of material from one to another.

 

8. Cytosol of all eukaryotes cells contains a network of fibers called the cytoskeleton, a network of fibers that supports the cell and helps to organize cellular components. The cytoskeleton includes microtubules, intermediate filaments, and microfilaments.

 

9. Lactate dehydrogenase (LDH) is a marker enzyme of cytoplasm, an important enzyme of the anaerobic metabolic pathway.