What are the tiny blood vessels that allow transfer of gases and nutrients between tissues and blood?

Capillary vessels are indeed the tiny blood vessels that play a crucial role in the exchange of gases, nutrients, and waste products between the blood and the tissues. They are the smallest blood vessels in the circulatory system, with walls that are only one cell thick. This thinness allows for efficient diffusion processes, facilitating the transfer of oxygen and carbon dioxide as well as nutrients from the blood into cells and waste products from the cells back into the blood.

The structure of capillaries, combined with their extensive surface area, makes them ideally suited for their function in the circulatory system. They connect the end of arterioles, which carry blood away from the heart, to venules, which return blood to the heart. This network provides the necessary interface for metabolic exchanges to occur. As such, they are integral to maintaining homeostasis and supporting cellular function.