Difference Between Mitochondria and Plastids

Main Difference

The main difference between the mitochondria and plastids is that the mitochondria is a double membranous and containing fluid-filled sac organelle that helps in energy production and cell respiration whereas plastids are a double membrane and fluid-filled organelle present only in plants which involve in photosynthesis and storage of food.

Mitochondria vs. Plastids

Mitochondria are involved in cell respiration as well as in energy production as the production of ATP while plastids are involved in food storage as they store glucose in the form of starch and they also help in the photosynthesis reaction. Mitochondria are found both in animals and plants while plastids are found in plants only. Mitochondria are smaller in size on the other hand plastids are larger in size. There are no pigments in mitochondria whereas pigments are found in plastids. Mitochondria help in energy production whereas plastids help in food storage. Completely separated channels are present inside the matrix of mitochondria, but in the case of plastids, there are no separated channels. Mitochondria have their DNA inside whereas in case of plastids; the only chloroplast has their DNA. Mitochondria are involved in cellular respiration, and ATP production on the other side plastids are engaged in the process of photosynthesis, in giving the color to flowers and fruits and storage of proteins, starch, and lipids.

Comparison Chart

MitochondriaPlastid
Mitochondria is a double membrane organelle and consist of matrix and cristaePlastid is also a double membrane organelle, present in plants and contains pigments
Occurrence
Mitochondria present in all types of eukaryotic cells either animals or plantsPlastids are present only in plants
Structure of Inner Membrane
Many folds are present in inner membranes which are known as cristaeNo folds are present in the inner membrane
Size
They are smaller in sizeThey are larger in size
Presence of Pigments
No pigments are found in mitochondriaPigments are found in plastids
Structure of Matrix
Separated chambers are present in the matrix of mitochondriaPlastids do not contain separate chambers in the matrix
Production
Mitochondria produces ATPPlastids produce glucose and store it in the form of starch
Functions
They are involved in cell respiration and energy productionPlastids are involved in photosynthesis

What is Mitochondria?

Mitochondria are also called as the powerhouse of the cell. Mitochondria is that organelle which is involved in the production of energy in the cell. The ATP is a kind of currency for the cell and is used in aerobic respiration. Mitochondria contain the cristae and matrix. This organelle is present in all cells of animals and plants. Cristae are the inner membrane folds, and they give the more surface area for the production of ATP. Matrix is also found inside the mitochondria, and it is a gelatin type substance. Many separated channels are located in the matrix. Mitochondrial DNA is found in the matrix which is involved in many types of cell chemical reactions and also helps in protein synthesis. The citric acid cycle of cellular respiration also takes place in the matrix of mitochondria. But the last steps of cellular respiration of the oxidative phosphorylation and electron transport chain takes place in cristae of mitochondria. Mitochondria vary in sizes and number according to the location of mitochondria present in which type of cell.

Functions

  • Cellular respiration of cell occurs in mitochondria.
  • It is the powerhouse of the cell as it produces energy like ATP.
  • They also store calcium.
  • They also play a role in cell signaling.
  • Mitochondria also involved in heat production and thermogenesis.

What is Plastid?

Plastids are double membranous organelles present only in plants. They are also fluid filled organelles. They usually contain pigments that store the food. There are three different types of plastids which are leucoplast, chloroplast, and chromoplast.

  • Leucoplasts: They are also known as white plastids as they have no color. They play a role in storing different kinds of molecules. They are also further divided into three types depending on the types of particles they store. Protoplasts (they store protein), Amyloplasts (they store starch), Elaioplasts (they store lipids).
  • Chloroplast: These type of plastids are green in color as they contain chlorophyll which plays a role in the photosynthesis. DNA is also present in these types of chloroplasts. Their internal membrane is also known as thylakoid. Thylakoid is surrounded by stroma.
  • Chromoplasts: They are red, yellow and orange in color. They are present in the petals of flowers and roots of some plants. The color of chromoplast is due to the presence of carotenoid pigments which may be carotenes or xanthophylls. They are formed in the result of the differentiation of other plastids. They give the color to different flowers and fruits. They are also helpful in the pollination as many insects attract due to the color of flowers.

Functions

  • Plastids are involved in the process of photosynthesis.
  • They store the food and different kinds of proteins and lipids and starch.
  • They give the color to flowers and fruits.

Key Differences

  • Mitochondria are energy production organelles while plastids are food storage organelle.
  • Mitochondria are present in all types of eukaryotic cells whereas plastids are found only in plants.
  • Mitochondria are helpful in cellular respiration on the other hand plastids are helpful in the process of photosynthesis.
  • In the case of mitochondria, ATP is produced while in case of plastids glucose is produced.
  • In mitochondria, the inner membrane is present in folds that are known as cristae while there are no folds found in case of plastids.

Conclusion

The conclusion of this article is that mitochondria are a double membrane, energy producer organelle found in both animals and plants whereas plastids are double membranous, fluid-filled organelle present only in plants for the process of photosynthesis.

Janet White

Janet White is a writer and blogger for Difference Wiki since 2015. She has a master's degree in science and medical journalism from Boston University. Apart from work, she enjoys exercising, reading, and spending time with her friends and family. Connect with her on Twitter @Janet__White

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