Question 20

Blood pumped from the heart first enters arteries that then narrow to form arterioles that deliver blood to capillaries of the organs.

The flow of blood from the heart to the organs follows a specific pathway where blood is pumped into arteries, which subsequently narrow into arterioles, leading to the capillaries that supply the organs.

A) Blood pumped from the heart first enters arteries that then narrow to form arterioles that deliver blood to capillaries of the organs

This option accurately describes the pathway of blood flow from the heart to the organs. Blood is indeed first pumped into arteries, which branch into arterioles and further into capillaries, allowing for nutrient and oxygen exchange with tissues.

B) Blood pumped from the heart first enters veins that then narrow to form venules that deliver blood to arteries of the organ

This option is incorrect as it misrepresents the flow of blood. Blood does not enter veins directly from the heart; rather, it leaves the heart through arteries. Veins are responsible for returning blood to the heart, not delivering it to the organs.

C) Blood pumped from the heart first enters arteries that then narrow to form arterioles that deliver blood to capillaries of the organs

This option is correct and accurately reflects the physiological sequence of blood flow. After being pumped from the heart, blood travels through arteries, which then branch into smaller arterioles that connect to capillaries, facilitating the exchange of gases and nutrients with the organs.

D) Blood pumped from the heart first enters arteries that then narrow to form veins that deliver blood to the organs

This option is incorrect as it inaccurately describes the blood flow pathway. Blood does not flow from arteries into veins to deliver blood to organs; instead, veins return deoxygenated blood back to the heart after the exchange of materials in the capillaries.

Conclusion

Option C is definitively correct as it accurately describes the flow of blood from the heart through arteries and arterioles to the capillaries of the organs. All other options either misrepresent the direction of blood flow or incorrectly describe the functions of veins and arteries, failing to depict the true physiological process. Understanding this pathway is essential for comprehending how oxygen and nutrients reach body tissues.