Do Mitochondria Have a Nucleus? 11 Facts You Should Know

Mitochondria are referred as batteries that help generating energy while interacting with nucleus of cell. Let us see if mitochondria is contained of nucleus.

Mitochondria consists of its own DNA that is distinct from the DNA of the nucleus of a cell. It is referred to as the mitochondrial DNA or mtDNA. This mitochondrial DNA is only carried forward via females because sperms do not contain mitochondria in them.

A very small quantity of “mitochondrial DNA” codes for each of the following mitochondria present in the cell. Only 0.1 percent of the entire human genome is made up of mitochondrial DNA, which is primarily transferred from mother to offspring.

For each cell, nuclear DNA can have only two copies of itself but mitochondrial DNA may be present in the form of thousand copies. Red blood cells of mammalians do not contain mitochondria in them. Whereas, lower species of vertebrates like reptiles, Aves and fishes have mitochondria in them.

What is mitochondrial DNA?

Mitochondrial DNA, denoted as mtDNA or mDNA is the DNA that is located in mitochondria. Let us discuss more about mitochondrial DNA.

Mitochondrial DNA, is a small portion of DNA that helps in converting food’s chemical energy into a special form that is helpful for the cells, like adenosine triphosphate (ATP). ATP is later utilized by the entire cell as a supply of chemical energy.

Mitochondrial DNA lg
Image Credit: Mitochondrial DNA – Wikipedia

All mitochondria contain a DNA in circular shape of about two to ten duplicates. Like other organelles, mitochondria consist of their individual non-nuclear DNA complement.

What is nuclear DNA?

Nuclear DNA or nuclear deoxyribonucleic acid also denoted as nDNA, is the DNA that is found in all nucleus of the cell of a eukaryotic species. Let us talk more about it.

Nuclear DNA is necessary in a way to store data or information in order to maintain the cell growth and various functions. For each of the cell there are about two duplicates of the nuclear DNA that is inherited from both the parents.  

nuclear dna
Image credit: Nuclear DNA – Wikimedia

Thus, we can say that nuclear DNA is passed down from both maternal and paternal genes. This kind of DNAs are different for every individual except for identical twins.

Relation between mitochondria and nucleus

Cellular process are regulated by intercellular communication between the nucleus and the mitochondrion. Let us see how mitochondria and nucleus are related in detail.

Both mitochondrion and nucleus plays a vital role that help the cells to function normally, such as maturation and stress adaption. If there is any malfunction between both organelles, then all the necessary functioning of the cell would come to an end and gradually the cell will be dead.

Mitochondria and nucleus need to work simultaneously because without the production of proteins whose genes are found in the cell nucleus, they are not capable to make energy and reproduce anymore or even survive.

Do mitochondria have a nucleus?

The mitochondria only have their own sets, that is, individual sets of DNAs in them. Let us see if mitochondria have a nucleus.

Mitochondria do not contain any nucleus or nuclei in them. They are present in cytoplasm of the cell just like the nucleus. They consist of their individual DNA in the sort of plasmids.

Why mitochondria and nucleus are absent in erythrocytes?

The erythrocytes or the red blood cells (RBCs) do not have organelles like mitochondria and nucleus in them. Let us discuss the reason behind it in detail.

The nucleus and mitochondria are absent inside erythrocytes because there is no need for the mature red blood cells or erythrocytes to get divided. This allows the cell to carry more hemoglobin in them.

The nucleus is absent inside erythrocytes as it occupies more space and thus reduces the capability of carrying oxygen in them. Since mitochondria is absent in red blood cells, oxygen is transferred directly to the places that is in need and it is not used up by the erythrocytes.

What do mitochondria have instead of a nucleus?

Just like the nucleus, the mitochondria contain its own double membranes. Let us see what mitochondria have instead of a nucleus.

Instead of having a nucleus, mitochondria consist of double membranes which are comprised of the phospholipid layer. The outer surface of the mitochondrion is covered by the outer membrane. The inner membrane is situated deep inside and consist of several folds known as the cristae.

mito structure
Image Credit: Structure of mitochondria – Wikipedia

Both the membranes help the mitochondrion in the production of energy. Chemicals inside the cell must be transformed, or they must go via pathways, in order to produce that energy.

Up to 75% of the membrane’s composition is protein, making the mitochondrion, which is a cell organelle, that metabolizes substances the fastest.

Are mitochondria present in both plant and animal?

The only distinction between plant and animal cells is that plant cells contain chloroplasts along with mitochondria in them. Animal cells lack chloroplast. Let us proceed with it.

Almost all the aerobic cells like plant and animal cells have mitochondria in them. In both plant and animal cells, the role of mitochondria is to generate cellular energy through the Krebs cycle, that helps in the production of ATP.

These mitochondria are colorless cell organelles which is thoroughly spread in the surface of cytoplasm.

Are mitochondria present outside the nucleus of a plant cell?

A few genes are found outside the nucleus in the plants’ cell organelles. Let us see if mitochondria are present inside or outside the nucleus of a plant cell.

Mitochondria are present outside the nucleus of a plant cell such that it helps in producing energy for the cell. Along with mitochondria, chloroplast is also found outside the nucleus which helps in carrying out the process of photosynthesis in plant cells.

Is nucleus present in all cells having mitochondria?

Nucleus is considered as the brain of the cell as it contains all the genetic information in it in the form of DNA. Thus, it has to be present in all cells. Let us see in details.

Nucleus is present in all cells be it eukaryotes or prokaryotes along with mitochondria. But mitochondria are not present in every cells. Mitochondria are sometimes present in eukaryotes only along with nucleus. Prokaryotes like bacteria and some other species do not have mitochondria in them.

How are mitochondria separate from cell nucleus?

Mitochondria and nucleus can be separated or differentiated in the following ways:

Mitochondrial DNANuclear DNAMitochondrial DNA codes for the genetic materials which is needed for mitochondria itself.Nuclear DNA codes for the genetic information which is necessary for the whole cell.
Mitochondrial DNA is present within the mitochondria.Nuclear DNA is situated within the cell’s nucleus.
An entire cell consists of about 0.25% of mitochondrial DNA and has 16,569 bp.An entire cell consists of about 99.75% of nuclear DNA and has around 3.2 billion bp.
Mitochondrial DNA grows and gets mutated at a pace of twenty times higher.Nuclear DNA has a lesser rate of mutation.
Mitochondrial DNA is circular in shape and smaller in size.Nuclear DNA is linear in shape and larger in size.
Mitochondria have numerous copies of its mitochondrial DNA.Nuclear DNA contain a small number of copies of its own in the nucleus of human cell.
All the mitochondrial DNA is inherited from mother and nothing from father.Nuclear DNA is passed down both from mother and father to the offspring.
Mitochondrial DNA is only helpful in a way to check maternal lineage and it cannot be used to check paternal lineage.Nuclear DNA is used to check lineage in an individual.
In the organelle mitochondrial DNA is present inside the matrix.Nuclear DNA is found enclosed or covered inside a membrane.
Mitochondrial DNA as a chromosomal pairing which is haploid in nature.Nuclear DNA has a chromosomal pairing which is diploid in nature.
Mitochondrial DNA lack process such as generational recombination and replication repair. Generational recombination and replication repair are present in nuclear DNA.
Difference between mitochondrial DNA and nuclear DNA

What do mitochondria share with the nucleus?

Mitochondria and nucleus also have some features in common. They are given below:

  • According to recent research, mitochondria provides energy while interacting with the nucleus of cells in delicate ways that have never been observed in people.
  • Both nucleus and mitochondria are present in the cells of eukaryotes. They are absent in cells of prokaryotes such as bacteria and archaea.
  • Both of them consists of DNA.
  • The chromosomes of the cell is found inside the nucleus while mitochondria consists of the mitochondrial genome.
  • They both are considered as the organelles that are present inside the cell.
  • The mitochondria have protein-lined membrane pores while the nucleus have double cell membrane.

Conclusion

There is no recombination between the maternal and paternal genomes because mitochondrial DNA is inherited exclusively from the mother as a connected collection of genes that are passed on to offspring in the cytoplasm of the egg cell.

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