Function is high in the presence of cardiorespiratory fitness.

Mitochondrial oxidative phosphorylation is the major pathway for ATP production in eukaryotic cells.

Primary site of ATP production in aerobic respiration.

Mitochondria are known as the powerhouse of the cell is a double membrane bound cell organelle that functions for the production of energy or ATP within the cell. 

Specifically, the mitochondria is where the Krebs cycle or TCA cycle for the production of NADH and FADH occurs, producing within the electron transport chain (ETC) and oxidative phosphorylation for the final production of ATP.

Cellular redox energy from the breakdown of food is converted to a proton gradient across the inner mitochondrial membrane which is dissipated to catalyze the formation of ATP.

Mitochondrial respiration is coupled to the formation of the proton motive force, and the dissipation of the proton motive force is closely linked to the synthesis of ATP.

Mitochondria generate most of the cell’s supply of adenosine triphosphate (ATP), a source of chemical energy. 

A hub for multiple signaling pathways intersecting energy production, survival control, and oxidative stress.

Mobile organelles that exist in dynamic networks.

Mitochondria convert energy for the cell into a usable form, adenosine triphosphate (ATP).

To function cells require ATP production by mitochondria.

Mitochondria continuously joined by the process of fusion and divide by the process of fission.

The mitochondrion is a component of a human cell, and contains its own DNA. 


Mitochondrial DNA usually has 16,569 base pairs (the number can vary slightly depending on addition or deletion mutations,and is much smaller than the human genome DNA which has 3.2 billion base pairs. 


Mitochondrial DNA is transmitted from mother to child, thus a direct maternal ancestor can be traced using mtDNA. 

Each mitochondrial organelle typically contains between 2 and 10 mtDNA copies. 


During cell division the mitochondria segregate randomly between the two new cells, and make more copies, normally reaching 500 mitochondria per cell. 


As mtDNA is copied when mitochondria proliferate, they can accumulate random mutations (heteroplasmy).


Mitochondrial disease may become clinically apparent once the number of affected mitochondria reaches a certain level; this phenomenon is called threshold expression.


More than 270 pathogenic variants of mtDNA have been reported.


Mitochondria generate ATP, and have important roles in adaptive thermogenesis, ion homeostasis, immune responses, reactive oxygen species, and apoptosis.

Mitochondria are intracellular organelles necessary for cell function and survival.

The inheritance of mtDNA Is distinct from autosomaldisorders: there is a coexistence of normal and pathogenic variants within the cells affected by mtDNA diseases.

Mitochondrial genome is present in thousands of mtDNA copies in the normal cell and the number of mutant genomes must reach a critical  threshold in order to cause cellular dysfunction and mitochondrial disease.

Crucial for the synthesis of adenosine triphosphate (ATP), the major form of cellular energy.

In addition to the generation of reactive oxygen species, mitochondria are also involved with life-sustaining functions including calcium homeostasis, PCD, mitochondrial fission and fusion, lipid concentration of the mitochondrial membranes, and the mitochondrial permeability transition.

Major structures of mitochondria include the inner and outer mitochondrial membranes, cristae, and electron transport chain.

Cardiolipin is a unique phospholipid exclusive to mitochondria and present only in the inner membrane of mitochondria, and acts as a linchpin to hold together the respiratory protein complex subunits (complexes I, II, III, and IV) that are essential to achieve optimal functioning of numerous enzymes involved in mitochondrial energy metabolism.

Crucial for the synthesis of adenosine triphosphate (ATP), the major form of cellular energy.

Cardiolipin acts to holds together the respiratory protein complex subunits of the electron transport train that are essential to achieve optimal functioning of numerous enzymes involved in mitochondrial energy metabolism.

Contain their own DNA which encodes 13 mitochondrial proteins, 2 ribosomal RNAs and 22 transfer RNAs.

Cell injury frequently associated by morphologic changes in mitochondria.

Damage caused by oxidative stress, increased Ca++, by phospholipid breakdown via phospholipase A2 and sphingomyelin pathways, and by lipid breakdown products free fatty acids and ceramide.

Reactive oxygen species (ROS) are regarded as unwanted by-products of oxidative phosphorylation in mitochondria.


 It is proposed that substances which inactivate ROS, such as antioxidants, would lead to a reduction of oxidative stress and thereby produce an increase in lifespan.

The outer membrane contains proteins which allow the transport of large molecules for oxidative respiration.

The inner membrane is selectivley permeable and has a large surface area with folds, the cristae.

Cristae contain enzymes and other molecules that carry out energy producing reactions of the

Transmembrane proteins maintain the selectivity of the inner membrane and comprise the electron transport chain and maintain a proton gradient between the intermembrane space and the inner membrane.

Matrix granules function as binding sites for calcium and contain some DNA and ribosomes.

Contain more than 1500 different proteins.

Damage leads to increased mitochondrial permeability and prevents maintenance of membrane potential critical for oxidative phosphorylation.

Myocardial ischemia leads to increased mitochondria Ca++ uptake, which increases permeability and leads to breakdown of mitochondrial respiration and ultimately cell death.

Damage can be caused by leakage of cytochrome c into the cytoplasm .

Cells contain hundreds to thousands of mitochondria, but are lacking in mature erythrocytes.

Mitochondrial diseases heterogeneous and vary in clinical features that are caused by impaired function of the mitochondrial respiratory chain.
The underlying cause of such mitochondrial diseases can be gene mutations affecting the nuclear DNA or the mitochondrial DNA, both of which contain genes encoding components of the oxidative phosphorylation machinery required to generate ATP.

ATP is the currency of cellular energy.

For most patients with mitochondrial disease is only symptomatic treatment is available.
There are more than 300 distinct mitochondrial diseases occurring in the nuclear of mitochondrial genomes.
Mitochondrial disorders result from pathogenic variance in either the nuclear or mitochondrial DNA.
Most of these diseases are recessive conditions with decreased respiration.
Mitochondrial disease is typically manifest as severe and often lethal multisystem disorders.
Mitochondrial diseases affect 5-15 persons 100,000 patient population.
Mutations in mitochondrial DNA more commonly causes mitochondrial disease in adults than  do mutations in nuclear genes.
More than 2 pathological variants of mitochondrial DNA have been reported.

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