Name the cell organelle in which the breakdown of pyruvate to give carbon dioxide,water,and energy takes place.

Which is the correct sequence of parts in the human alimentary canal?

$(a)$ What happens to the heart when muscles work harder?
$(b)$ Which body system is directly affected when a person has heart disease?
$(c)$ Which cells increase in number during infection?

What will happen if platelets were absent in the blood?

Which organ secretes a hormone when the blood sugar rises? Name a digestive enzyme released by this organ.

What is the functional difference between the four chambers of the heart?