The intervertebral discs, which are between vertebrae, are the parts that prevent the vertebrae from grinding against one another.
The intervertebrals discs act as a cushion; they absorb the stress and shockw that occur during movement, preventing such grinding.
Electron transport trains create a concentration gradient of hydrogen ions outside the mitochondria and fewer inside the mitochondria and creates energy(ATP) by diffusing the hydrogen ions back in
Recall the endosymbiosis hypothesis and recall endosymbiosis. Remember that the very first cell was a prokaryotic cell. Which engulfed chloroplast precursors and mitochondria. We all come from these cells. And how we evolved over time shows the relationship. I'm a bio major hope I helped
The age group she does fit in is Infancy
Yy.yy is your answer ^-^
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