Answer:
DNA
Explanation:
Deoxyribonucleic acid or DNA is defined as the genetic material in all the living organisms responsible for all the genetic activities in an organism.
DNA carries genetic instructions that are inherited from one generation to another generation. The DNA comprises of genes having specific genetic code that encodes the sequence of amino acid residues in proteins. DNA undergoes the process of replication and form several copies of it which are passed on to next generation.
Hence, the correct answer is "DNA".
Respiratory system and the cardiovascular system
The atria and ventricles work together, alternately contracting and relaxing to pump blood through your heart. ... The electrical activity spreads through the walls of the atria and causes them to contract. This forces blood into the ventricles. The SA node sets the rate and rhythm of your heartbeat.