Which statement best describes enzymes?
(1) every enzyme controls many different
reactions.
(2) the rate of activity of an enzyme might
change as ph changes.
(3) temperature changes do not affect enzymes.
(4) enzymes are produced from the building
blocks of carbohydrates.

The best which describes an enzyme is 2.
 Every enzyme can control one or more types of reaction whereby the rate of activity of an enzyme will be influenced by PH and temperature.
Enzyme increases its reaction rate by lowering its activation energy. Some enzymes are being used commercially for example in the synthesis of antibiotics.

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.

Digestion because it removes waste