You do it this way; the shift in perspective can bewilder the reader. Consistency is the chief virtue here. There is, of course, a difference between a process essay that tells readers how to do something and a process essay that describes the process by which something gets done by someone else or by nature.here is, of course, a difference between a process essay that tells readers how to do something and a process essay that describes the process by which something gets done by someone else or by nature.
In the human heart, the pulmonary trunk (pulmonary artery or main pulmonary artery) begins at the base of the right ventricle. It is short and wideâapproximately 5 centimetres (2.0 in) in length and 3 centimetres (1.2 in) in diameter.
pulmonary arteries â deoxygenated blood is pumped by the right ventricle into the pulmonary arteries that link to the lungs. pulmonary veins â the pulmonary veins return oxygenated blood from the lungs to the left atrium of the heart. aorta â this is the largest artery of the body, and it runs the length of the trunk.