Scientists wanted to learn more about Griffith's experiment. They extracted a mixture of various molecules from the heat-killed bacteria. They found that (a) no longer occurred when they treated the mixture with enzymes that destroyed (b). This experiment supports the hypothesis that (c) is the genetic material.

Mitochondria is the cell organelle that produced the energy that is needed in the body system in form of atp, that is why it is called the power house of the cell. energy is needed by the living organisms to carry out the activities which sustain life.  if the mitochondria is destroyed atp will not be produced. if the mitochondria is destroyed, energy production will stop and the affected living organism will not have the energy to carry out the necessary life processes; this will lead to the death of the organism.

Ithink its because more have died recently than in the past.