Given below is the diagram of a human sperm. Read the information below the diagram and fill in the blanks: 
Human sperm are microscopic structures that carry genetic material. The sperm structure includes the head, middle piece, and tail, each with specialized functions.
(a) The acrosome is the cap-like organelle on the head of the sperm. It contains enzymes like Hyaluronidase that help dissolve the outer layer of the ovum to facilitate fertilization.
(b) The enzyme produced by the acrosome is Hyaluronidase, which dissolves the outer layer of the ovum during fertilization.
(c) The nucleus of the sperm has 23 chromosomes, which carry the genetic information required for the creation of a new individual.
(d) The middle piece of the sperm contains Mitochondria that provide the energy needed for the motility of the sperm, allowing it to swim towards the egg.
(e) Semen is a mixture of sperm and the fluids produced by the male accessory glands, which help nourish and protect the sperm during their journey to the egg.


During the ventricular systole, the atrioventricular valves (P) ________ and the semilunar valves (Q) _________.