Is cytoplasm an organelle?
Cytoplasm is a part of the cell but it is not an organelle. In fact, cytoplasm is the thick semi-fluid substance existing between the cell membrane and the nuclear membrane that covers the portion inside of the cell.
Organelles have a definite shape within the cell having a membrane or without membrane. On the other hand, cytoplasm is a thick gel-like solution that is concentrated with having various proteins, cytoplasmic inclusions, along with various other cell organelles dissolved or lied in it.
It is to be noted that cytoplasm is 85% water and is usually colourless in nature. It has neither a definite shape nor a definite volume.
In general, the composition of cytoplasm includes 85% water, 10-15% proteins, 2-4% lipids, along with nucleic acids, inorganic salts, and polysaccharides in smaller amounts. These things make the cytoplasm thick and highly viscous in texture.
The job of the cytoplasm is to provide a matrix inside the cell in order for the various stored nutrients, secretory products, pigment granules, proteins, enzymes, other cell organelles to remain inside the cell.
It helps maintain the shape of the cell, its cellular movement, material flow, and exchange in and out of the cell.
Also, note that the cytoplasm makes up about 9 portion out of the 10th of the entire cell.
The shape of the cytoplasm depends on the shape of the cell that is supported by the cytoskeleton.
And the contents/volume of the cytoplasm depends on the nature of the cell and its functionality.
It is to be strictly noted that the cytoplasm that includes the thick viscous fluid includes all of the material inside the cell and outside of the nucleus.
So, here we can very clearly state that cytoplasm is not a single thing. Iin fact, it is the sum-total of the cytosol (complex mixture of cytoskeleton filaments, dissolved molecules, and water), Cell organelles (membrane-bound structures inside the cell that have specific functions and shape), and Cytoplasmic inclusions (small particles of insoluble substances suspended in the cytosol) that are equipped together in the space between the cell membrane and nuclear membrane.
Why is cytoplasm not an organelle?
Cytoplasm includes the cytosol which is actually the jelly-like watery matrix of the cell that makes 70% of the cell volume. It is here in the matrix that the other cell bodies that are membrane-bound or with having definite structure lie and remain suspended for their functionality.
So, the cytoplasm is actually not a cell organelle but a matrix instead that makes up the volume inside of the cell and in which the cell organelles remain suspended.
Cell organelles are the cellular components that include both membrane and non-membrane bound organelles present inside the cells.
Whereas, cytoplasm is the matrix that is the jelly-like fluid cytosol in which the cell organelles remain suspended so that they can freely move, function, reduce friction, and use the cytosol matrix medium of the cytoplasm for communicating with each other and with the other organelles of the cell.
Now, that we know that the cytoplasm is not an organelle but a semi-fluid thin liquid substance, we must also know about the fact that the cytoplasm can remain like a thin fluidly liquid with less viscosity, and can also sometimes turn to a thick gel-like liquid with high viscosity.
Now, the turning of the cytoplasm into distinct thin fluidly liquid to thick gel-like liquid in most of the cases is due to the level of interaction between cytoplasmic components, cell organelles, and due to the increased proportion of dissolved cytoplasmic inclusions in it.
What is difference between cytoplasm and cell organelle?
Cytoplasm consists of cytosol, cell organelles, and various cytoplasmic inclusions. Cell organelles are present in the cytoplasm.
Cytoplasm is part of the cell between the cell membrane and nuclear membrane. On the other hand, the portion of the cytoplasm that is not contained inside the membrane-bound cell organelles is called the cytosol.
Cytoplasm is where all the metabolic reactions of the cell take place. Whereas, it is actually the interactions between the various cell organelles and the cytoplasmic inclusions that cause various metabolic reactions and cell signalling processes to occur in the cytoplasm.
Cell organelles have their own type of matrix bounded inside the organelle’s membrane, for example, the nucleus has a nucleoplasm matrix. Whereas, cytoplasm itself is the matrix that is contained within the entire cell membrane.
Membrane-bound organelles will have their own matrix. Whereas, cell organelles that don’t have any membrane will not have their own matrix and so they will directly use the cytoplasm as the matrix.
The cytoplasmic matrix (cytosol) may change from fluid (sol) to elastic (gel) and then back again to being fluid depending on the various metabolic activities going on inside the cell. But, the matrix inside any cell organelle may not always change from fluid to gel, and will only change under certain circumstances which are often rare to see.
Cytoplasm includes the various cell organelles, cytosol, fatty acids, amino acids, enzymes, proteins, and salt contents. Whereas, the Protoplasm contains both cytoplasm and nucleus with the nucleoplasm and this nucleus is the biggest cell organelle.
Waste products are also dissolved in the cytoplasm that will be soon be removed by exocytosis with or without the help of any other cell organelles. On the other case, the cell organelles don’t keep their waste products inside them as they just export the wastes to the cytoplasm where these will soon be removed out from the cell.
Cytoplasm provides shape, volume, and structure to the cell, whereas, cell organelles take part here by just being suspended in the cytoplasm.
Cytoplasm remains present and helps in mitosis and meiosis cell division. Whereas, all the other cell organelles except for centrioles, etc. disappear during the cell division process and only appear approaching cytokinesis.
So, Why does cytoplasm and nucleoplasm form in the cell?
Both cytoplasm and nucleoplasm, are together called the protoplasm. So, nucleoplasm is the part of the protoplasm that is enclosed by the nuclear membrane.
While, cytoplasm is the type of protoplasm that is placed between the cell membrane and the nuclear membrane and other cell organelles’ membrane.
Cytoplasm is necessary for the cell to home the various cell organelles including the nucleus so that the organelles are able to interact with the various cell organelles, cell inclusion, or with other cells through the cell signaling pathway.
On the other case, Nucleoplasm is very much essential to take care of what is going inside the nucleus itself by housing the nucleolus and chromatin fibres and making it possible to produce proteins that will help the nucleus interact with the various cell organelles, cells, etc. all through the cytoplasm.
Nucleoplasm is necessary for the eukaryotic cell to perform DNA transcription to mRNA, and DNA replication as well.
On the other case, Cytoplasm is necessary for the eukaryotic cell to perform translation of the mRNA that was produced in the nucleoplasm to various Amino acids, thus aiding in the synthesis of proteins respectively.
The nucleoplasm protects the sensitive and no-membrane-bound DNA materials from getting dissolved by the cell. And so, it stores the main genetic content of the cell called the DNA and facilitates an isolated, well-protected, and sensitively secure environment where controlled transcription and gene regulation are enabled.
If there would have been no nucleoplasm then these DNA and other genomic materials would have been remained suspended in the cytoplasm. And so, there would have been high chances that these genomic materials would have been destroyed in a few of the cases because the cytoplasm contains various other waste products that need to be removed out from the eukaryotic cell.
ANSWERED: What is Cytoplasm composed of?
Once again, let’s take a quick look into the components of the cytoplasm in short and easy to understand format:
- Cytosol: This is the gel-like thick viscous liquid that makes up the matrix of the cytoplasm and takes about 70% of the total volume of the eukaryotic cells.
- Cell Organelles: These are the cell’s internal sub-structures that may or may not be membrane bound. Example: Mitochondria, Nucleus, Golgi Bodies, Endoplasmic Reticulum, Ribosomes, etc.
- Cytoplasmic Inclusions: These are the intracellular non-living substances that remain suspended in the matrix of the cytoplasm, and these are produced due to the various metabolic activities of the cell organelles. Example: Starch, Proteins, Lipids, Pigments, Enzymes, etc.
At last, it is to be noted that the cytosol also includes the cytoskeleton, the ribosomes, and the centrosome along with all of the other macromolecules, micromolecules, and various other solutes that are present outside of the nucleus and also outside of the lumen of the various membranous cell organelles like Mitochondria, Endoplasmic Reticulum, Golgi Bodies, Vesicles, Endosomes, etc.