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Altitude, temperature, circadian rhythms and exercise
Published in Adam P. Sharples, James P. Morton, Henning Wackerhage, Molecular Exercise Physiology, 2022
Henning Wackerhage, Kenneth A. Dyar, Martin Schönfelder
The air we breathe today consists of 20.9% of oxygen (O2). However, this was not always the case. For almost half of the Earth’s history, oxygen was mostly less than 0.001%. This changed during the “great oxidation event” between 2.4 and 2.1 billion years ago which increased global oxygen levels. Oxygen-producing photosynthesis by plants consumed CO2 and generated O2 (2). This dramatic change in the gas concentrations of the atmosphere allowed for the evolution of new species that consumed O2 and generated CO2.
CRISPR/Cas: from adaptive immune system in prokaryotes to therapeutic weapon against immune-related diseases
Published in International Reviews of Immunology, 2020
Juan Esteban Garcia-Robledo, María Claudia Barrera, Gabriel J. Tobón
The biosphere as it exists today is the result of interactions among chemical elements, environmental conditions, and the evolution of various life forms over the past several billion years [1, 2]. The earth formed approximately 4.5 billion years ago [3], and since its creation has undergone marked changes in geology and atmospheric composition [4], most importantly the rise of atmospheric oxygen, known as “The Great Oxidation Event” (GOE) [5] concomitant with the appearance of the first photosynthetic organisms, the oceanic cyanobacteria, about 2.3 billion years ago [6]. Eukaryotic organisms emerged later, about 1.7–2.7 billion years ago, according to paleontological records [7, 8]. The most widely accepted hypothesis on the evolutionary progression from prokaryotes to multicellular eukaryotes posits that GOE exerted positive evolutionary pressure on archaea due to the development of potentially damaging reactive oxygen species, driving the selection of species capable of conserving the integrity of their metabolic pathways and genetic information via the development of membrane-bound intracellular compartments such as the cell nucleus [9].