The answer is microevolution.
<span>Nitrogen fixation is made by numerous prokaryotes, including bacteria, actinobacteria, and certain types of anaerobic bacteria. Organisms that fix nitrogen are called Diazotrophs.</span>
<span>The pH of the matrix increases and the pH of the inter membrane cell decreases
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The reason behind this is the presence of the electron transport chain within the mitochondria which requires the transport of hydrogen ions. The movement of hydrogen ions results in varying pH. If the mitochondria dies, the hydrogen ions will not move into the matrix, causing its pH to increase, and they will build up in the inter membrane causing a decrease in pH.
C. Organ System
Like said in the definition above, an organ system is a group of organs working together to perform a specific function for the organism.
hope this helps !! have a great day :))