Difference Between Mitochondria and Plastids (With Table)

A cell is the structural and functional unit of life. A cell is divided into three main parts called the cell membrane, the nucleus, and the cytoplasm. A cell membrane’s function is to keep the chemical reactions of a cell together. The cellular fluid, in which the chemical processes of life/cell occur is the Cytoplasm. Basically, cells are of two types – Eukaryotic and Prokaryotic cells. Both the cell type differs on the basis of Mitochondria and Plastids.

Mitochondria vs Plastids

The difference between Mitochondria and plastid is that Mitochondria is found in Eukaryotic cells, whereas Plastids are found only in Prokaryotic or plant cells. Mitochondria is comparatively smaller in size than Plastids.

Mitochondria are very widely also known as the powerhouse of the cell, as it produces cell energy i.e., ATP (adenosine triphosphate). Mitochondria are found in the cytoplasmic area of the cell and are membrane-bound. Mitochondria are said to be originated from the Prokaryotic cells but it is only found in Eukaryotic cells.

While plastids are cell organelles that are membrane-bound and are found generally in plants, fungi, algae, etc. Plastids are the manufacturing as well as the storage unit of the cells of the plants that produce their food by themselves with the help of sunlight i.e., Autotrophic. Plastids are comprised of various plant pigments or colours too.

Comparison Table Between Mitochondria and Plastids

Parameters of ComparisonMitochondriaPlastids
OccurrenceIt is found in eukaryotic cells only. It is found in prokaryotic and plant cells.
FunctionIts basic function is cellular respiration in plants. Its basic function is for the photosynthesis in the main cell organelle or in plants
SizeIt is small in sizeIt is bigger in size compared to mitochondria.
ProductsIts product is energy in the form of ATP. Its product is glucose in the form of starch.
Presence of pigmentsIt has the presence of no pigments. It has different types of multiple pigments present.

What is Mitochondria?

Carl Benda coined the term ‘Mitochondria’ in the year 1898. A mitochondrion is a cell organelle that is double membrane-bound. It is found in the cytoplasmic area of the Eukaryotic cells. It is the centre of energy generation and assimilates the nutrients and liberate chemical energy in the cell in the form of ATP (Adenosine Triphosphate). The mitochondria also regulate the growth and death of the cells, it also indicates the cells and generates heat. Mitochondria play an important role in cellular respiration.

The process by which ATP is created in the body is called Anaerobic fermentation, an exception is an anaerobic fermentation does not take place in the mitochondria of the cell. The fundamental need of mitochondria to generate ATP is glucose and oxygen. The energy generated through mitochondria is more than the energy created by anaerobic fermentation. In animals, mitochondria are oval or round in shape. Mitochondria is double membraned and is composed of proteins and phospholipid bilayer.

Mitochondria has Five different parts: Outer membrane, inner membrane, inner membrane space, cristae, Matrix. Outer Membrane keeps the inner cell organelles tight/intact in place. Inner Membrane has essential enzymes that catalyze the production process of ATP. Inner Membrane Space is the space between the inner membrane and the outer membrane of the mitochondria. Cristae is the inner membrane of the mitochondria has a lot of folds; those folds are known as Cristae.

Matrix is the space apart from the cristae in the inner membrane is known as the Matrix. The function of mitochondria is to convert food into ATP/energy and elimination or remove wastes from the mitochondrial cell. Mitochondria and bacteria have a lot of common features. RBCs do not possess any mitochondria.

What is Plastid?

Plastids were first discovered by Ernest Haeckel; their basic definition was first proposed by A.F.W Schimper. Plastids are the manufacturing as well as the storage unit of the cells of the plants that produce their food by themselves with the help of sunlight i.e., Autotrophic in nature. Plastids have a lot of pigments which can be seen in plants & algae.

There are a huge number of pigments but the basic pigments of plastids are Chloroplast, Chromoplast, leucoplasts, proplastids. Chloroplasts are plastids that have chlorophyll i.e., a green pigment, which helps in the process of photosynthesis is called Chloroplast.

Chromoplasts has more coloured pigments other than the green pigment. Rhodoplasts or phycoerythrin is a red pigment. Phaeoplasts or carotenoids and Xanthoplasts or xanthophyll are the yellow pigments. Leucoplasts are the colourless plastids present in the parenchyma of the cells of the plant or leaves. It can be altered into pigmented or coloured plastids when subjected to sunlight. Proplastids has no colour and is not mature.

The meristematic cells having the minor vesicular structure are known as Proplastids. Chloroplast is filled with a liquid known as the stroma. In the stroma, highly organized membrane structures are present and they are known as grana. Other than grana, the stromatic fluid contains a host of plastid DNA, RNAs, enzymes and 70s ribosomes.

Main Differences Between Mitochondria and Plastids

  1. Mitochondria is only found in the eukaryotic cells, whereas plastids are present in prokaryotic and plant cells.
  2. The product of Mitochondria is ATP, whereas the product of Plastids is glucose, which is stored as starch.
  3. The function of the Mitochondria is cellular respiration, whereas the main function of plastids is for photosynthesis in the main cell organelle.
  4. Mitochondria is tinier in size, whereas Plastids are comparatively bigger in size.
  5. Mitochondria has no pigments present, whereas plastids have multiple pigments.

Conclusion

Mitochondria and Plastids both are a part of a cell. The only major difference is Mitochondria is not found in prokaryotic and plant cells, and Plastids are not present in Eukaryotic cells. Mitochondria is one of the important parts of a eukaryotic cell as it generates energy.

Plastids are one of the important parts of a prokaryotic cell because of the role it plays in catering pigment to the plants or leaves. Therefore, both are important and unique in their own place and are essential components in the functioning of the cell.

References

  1. https://www.pnas.org/content/112/33/10177.short
  2. https://www.sciencedirect.com/science/article/pii/S0074769608604155
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