Which of the following statements concerning the circulatory system is true?
**Core Concept**
The circulatory system, comprising the heart, arteries, veins, and capillaries, is responsible for transporting oxygenated blood and nutrients to tissues and removing deoxygenated blood and waste products. The system's efficiency is crucial for maintaining optimal oxygenation and nutrition of cells.
**Why the Correct Answer is Right**
The correct answer is related to the concept of peripheral resistance, which is the opposition to blood flow in the systemic circulation. The primary determinants of peripheral resistance are the resistance offered by the blood vessels, particularly the arterioles, and the viscosity of blood. In healthy individuals, the arterioles are able to constrict or dilate to regulate blood pressure and flow. The correct answer is likely related to the fact that peripheral resistance is a major factor in determining blood pressure.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe a fundamental principle of the circulatory system. While cardiac output is an important determinant of blood pressure, it is not the primary factor.
**Option B:** This option is incorrect because it is too broad and does not specifically relate to the circulatory system. Blood pressure is indeed influenced by cardiac output, but this is not the most accurate answer.
**Option C:** This option is incorrect because it is unrelated to the circulatory system. The concept of peripheral resistance is specific to blood flow and pressure, not to the nervous system.
**Clinical Pearl / High-Yield Fact**
Peripheral resistance is a key regulator of blood pressure and flow. The arterioles, which are the smallest branches of arteries, play a crucial role in regulating peripheral resistance through vasodilation and vasoconstriction.
**Correct Answer:** D.