Final answer:
The high pressure part of the circulatory system is the systemic circulation, where oxygenated blood is delivered to the body by the left ventricle. The low pressure part is the pulmonary circulation, carrying deoxygenated blood to the lungs. Systolic pressure, the high point of blood pressure, should typically range between 100 to 120 mm Hg in a healthy adult at rest.
Step-by-step explanation:
High Pressure and Low Pressure in the Circulatory System
The human circulatory system is comprised of two primary circuits: the systemic circulation and the pulmonary circulation. Systemic circulation is responsible for delivering oxygenated blood from the left ventricle through the aorta to the rest of the body, and this part of the circulatory system exhibits high pressure. Pulmonary circulation carries deoxygenated blood from the right ventricle to the lungs for gas exchange. Here, the pressure is relatively lower compared to the systemic circulation.
When the heart contracts during systole, blood is ejected into the arteries, creating arterial blood pressure. This pressure is known as systolic pressure and ranges from 100 to 200 mm Hg, with a desirable range being 100 to 120 mm Hg. The heart's relaxation phase, or diastole, reduces pressure as the chambers fill with blood again. As blood moves through the arteries and into smaller vessels such as arterioles and capillaries, the pressure continuously drops. This drop in pressure is mainly due to the resistance provided by these smaller blood vessels. The lowest pressure occurs when the blood returns to the heart via veins, completing the circulation loop.
Long-term deviations from the normal blood pressure ranges can have significant medical implications, as they may indicate underlying health issues. These pressures are a vital factor in the overall function of the circulatory system, affecting the flow of blood to various organs within the body.