Question

Differentiate between pulmonary artery and pulmonary vein.

Answer 1

Hint: The arteries and veins are the blood vessels which are responsible for the transportation of the oxygenated and deoxygenated blood all throughout the body.

Complete answer:
Arteries and veins are the types of blood vessels which perform the function of carrying blood to and from the heart. Arteries are those blood vessels which carry the pure or oxygenated blood from heart to all the organs of the body and blood flows under high pressure, except pulmonary artery.
Veins are the blood vessels in which impure or deoxygenated blood flows from all the organs and tissues of the body to the heart and then to lungs for purification, blood flows under low pressure and valves are present to prevent the backflow of the blood. Exception is the pulmonary vein.

Pulmonary artery	Pulmonary vein
It is the only artery which carries the deoxygenated blood.	It is the only vein which carries the oxygenated blood.
Flow of blood is towards the lungs from the right ventricle of the heart.	Flow of blood is towards the left auricle of the heart from the lungs.
Its wall is thick.	Its wall is thin.
Presence of valves is there.	The valves are absent in the pulmonary veins.

Note: The word pulmonary is related to the lungs and arteries and vessels are blood vessels that performs the function of transportation of blood, so the flow will be either towards the lungs or from the lungs and also these are the exceptional arteries and veins which carries deoxygenated and oxygenated blood respectively.