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
Matrix are within the inner membrane of the mitochondria.
Answer:
Mechanical barriers — which include the skin , mucous membranes , and fluids such as tears and urine — physically block pathogens from entering the body. Chemical barriers — such as enzymes in sweat , saliva , and semen — kill pathogens on body surfaces.
