Is the dna of every single living thing made up of adenines, thymines, cytosines, and guanines? what does that say about all living organisms?

The DNA (deoxyribonucleic acid) is a hereditary molecules, which is passed from one generation to another. A DNA molecule is made up nucleotides, each nucleotide is made of a sugar, a phosphate group and a nitrogenous base.

There are 4 types of nitrogenous bases present in the DNA, adenine, guanine, cytosine and thymine.

All the organism are made up of DNA only, which suggest that all the organism are derived from a single ancestor, as on the molecular level all the organism have a single type of molecules which determines all the traits in the organism.

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.