Differentiate between the following
Mitral valve and tricuspid valve(structure)
Artery and vein (direction of blood flow)
The right atrium and left atrium (nature of blood)

Hint: The bicuspid valve is the other name of the mitral valve.Blood is collected from various parts of the body via small blood vessels, and blood returns into the right atrium. It is said that all the arteries carry oxygenated blood pulmonary arteries is an exception to this. Veins carry oxygen-free blood, but the pulmonary vein is an exception

Complete answer:
Mitral valve and tricuspid valve(structure) -The atrioventricular opening between the left atrium and the left ventricle is protected by a bicuspid valve, also known as the mitral valve (with two valves). The right atrioventricular opening is protected by the tricuspid valve because there are three valves.
Artery and vein (direction of blood flow)
Arteries: Arteries are wide, elastic, thick-walled vessels that carry blood away from the heart to the limbs and organs of the body. They have thick, rigid walls to withstand high blood pressure leaking from the heart.
Veins: Veins carry blood from tissues and organs back to the heart. Blood in the veins flows under lower pressure than in the arteries. Therefore, veins do not have thick walls. But veins can hold more blood.
In short, we can say that Arteries distribute blood from the heart to various parts of the body. Veins collect blood from different parts of the body and pour it into the heart.
The right atrium and left atrium (nature of blood) -The pulmonary vein carries this oxygenated blood from the lungs to the left atrium when it relaxes. When the left atrium of the heart contracts, blood is transferred to the left ventricle of the heart, which expands. Deoxygenated blood is collected from various parts of the body via small blood vessels. They open up into larger blood vessels that carry blood back into the right atrium.
In short, we can say that the left atrium receives oxygenated blood while the right atrium receives deoxygenated blood.

Note:
Double circulation is a type of circulation which involves two circulations. Systemic circulation involves oxygenated blood movement from the left ventricle to the aorta. Then it is carried from the blood to the tissues through a network of arteries, arterioles, and capillaries. Oxygen-free blood is drawn from the tissues from the venules, veins and vena cava and emptied into the right atrium. Pulmonary circulation involves the movement of oxygen-free blood from the right ventricle to the pulmonary artery, which then carries blood to the lungs for oxygen supply. Oxygenated blood is transported from the lungs by the pulmonary vein to the left atrium, so the blood must flow through the lungs and tissues one by one in a double sequence.