Mighty but tiny energy houses in our cells -mitochondria

None of the 30 trillion cells that make up the human body, can be seen with a naked eye. Most of these tiny cells, have an even tinier energy producing “organelles”. These are our “mitochondria”. Cells that forms the heart muscle, have about 8000 of these in each cell, while cells in our other muscles have a few hundreds of them.

A 1967 postage stamp from Japan pictures a mitochondria. Also seen in this postage stamp are other micro-structures inside a cell – Ribosome and Endoplasmic reticulum.

These mighty power-houses, enable each cell to function. Almost all oxygen we breathe, and most glucose from the food we eat, is used by our mitochondria to generate energy. The vastness of this enterprise can be judged form needs of a resting human being, which is a minimum of 200ml of oxygen per minute, and 200gm of glucose per day.

First day cover of 1967 postage stamp. Mitochondria are elongated bean like structures that have an outer lining and an inner convoluted membrane. This is shown on the first day cover

Mitochondria were first seen in insect cells, towards the turn of the century. Most advanced microscopes at that time, saw them as small threads. German pathologist Richart Altmann identified them as an “organelle” in 1890, and in 1898 another fellow microbiologist Carl Benda coined the term “mitochondria” meaning “thread granule” in Greek. By 1939 concepts of cellular respiration were elaborated, and we knew that cells use oxygen and glucose to produce ATP, a cellular unit of energy. Details of mitochondrial structure, however was quite elusive.

This 1999 postage stamp from Romania shows electron microscope and its creator – A German Physicist Ernst Ruska. In 1931, he demonstrated that a magnetic coil could act as a lens and used several coils in a series to build the first Electron microscope in 1933. He was awarded Nobel Prize for this work in 1986, barely two years before his death.

Electron microscopy helped to show small unseen structures. Meanwhile in 1930, a Belgian biologist Albert Claude developed a technique that could separate out tiny components of a cell. He was the first to employ the electron microscope in the field of biology. By 1945 he described various cell structures such as mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosomes.

Albert Claude in a 1987 Postage stamp from Belgium. He had no formal secondary education, however he was allowed in the medical school due to a law that enabled war veterans of first world war to pursue higher education without diploma or other examinations.
Albert Claude on a first day cover of the 1987 postage stamp from Belgium. Claude was awarded with a Nobel prize in 1974 with George Palade and Christian de Duve “for their discoveries concerning the structural and functional organization of the cell”

In 1952, first detailed images of mitochondria were seen. This confirmed its double membrane and folded up ridges. Philip Siekevitz, a biologist and a colleague of George Palade coined the term “power-house” of a cell in 1957.

Oxygen is vital for us. As soon as oxygen levels in our body go down, a chemo-neurological reaction is triggered in our bodies. This reaction leads to our heart and breathing become faster. This reaction was elaborated by Corneille Heyman, another Belgian physiologist, who won 1938 Nobel Prize for this discovery. In 1987 when Belgium issued a postage stamp on Albert Claude, they also Honoured Heymann with one.

A 1987 stamp from Belgium on Corneille Heyman. The cancellation features both Claude and Heyman.
First day cover of Corneille Heymans postage. stamp. He was awarded a Nobel in 1938 for his discovery of the regulatory effect on respiration of sensory organs associated with carotid body and aortic arch.

As the power plants in virtually every human cell mighty mitochondria play an essential role in creating energy to drive cellular function and basically all of our biological processes. Nearly all cells have these sausage-shaped structures. Recent discoveries have connected malfunctioning mitochondria to Parkinson’s, heart disease, diabetes, and even some cancers.

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