Final answer:
The venous system carries mostly deoxygenated blood and has thinner walls with valves, while the arterial system carries mostly oxygenated blood and has thicker walls without valves. The arterial system operates under higher pressure than the venous system.
Thus, statements 1, 2, and 3 are correct.
Step-by-step explanation:
The venous system and arterial system have distinct properties and functions within the circulatory system:
- Venous systems generally carry deoxygenated blood back to the heart, except for the pulmonary veins which carry oxygenated blood from the lungs to the heart. In contrast, arterial systems typically carry oxygenated blood away from the heart to the body, except for the pulmonary arteries which carry deoxygenated blood to the lungs.
- The walls of the venous system are indeed thinner compared to those of the arterial system because veins operate under lower pressure and don't need to withstand the high pressure of blood pumped directly from the heart.
- Venous systems have valves to prevent backflow of blood, which are especially important in the limbs to assist blood return to the heart against gravity. In contrast, except for semilunar valves at the base of the large arteries leaving the heart, the arterial system does not contain valves within its major branches, as the blood pressure is sufficient to prevent backflow.
- Contrary to the statement, the arterial system has higher pressure compared to the venous system. Blood in the arteries is pumped directly from the heart, creating a high-pressure system, whereas by the time blood reaches the veins, it has lost much of this pressure.
Thus, statements 1, 2, and 3 are correct, whereas statement 4 is incorrect as the arterial system has higher pressure compared to the venous system.