Which of the following accurately describes venules?

Venules are small blood vessels that play a critical role in the circulatory system by collecting deoxygenated blood from capillaries and directing it back toward the heart. These vessels are typically formed when capillaries converge, allowing for the drainage of blood that has delivered its oxygen and nutrients to surrounding tissues and picked up carbon dioxide and metabolic waste.

The structure of venules is characterized by thin walls, which facilitates the exchange of fluids and small molecules. As blood returns from the capillaries, it enters the venules before progressing to larger veins that ultimately lead back to the heart. This positioning within the venous system is essential for ensuring efficient circulation and maintaining overall blood flow.

In contrast to other types of blood vessels, venules specifically do not deliver oxygenated blood; rather, they are responsible for carrying blood low in oxygen back toward the heart, making them crucial in the systemic circulation process. Understanding the function of venules helps clarify their role in maintaining the balance between oxygen supply and demand in the body's tissues.