What types of blood are found in capillary samples?

Capillary blood samples consist of a mixture of blood from various sources. When blood is collected from capillaries, it typically includes components from tissue, arterial, and venous blood due to the anatomical and physiological characteristics of capillaries.

Capillaries are the smallest blood vessels and serve as the exchange sites between the blood and surrounding tissues. Arterial blood flows into capillaries, delivering oxygen and nutrients to the tissues. In contrast, venous blood, which is depleted of oxygen and enriched with carbon dioxide and metabolic waste, returns through the capillaries as blood moves back to the venous system. Additionally, interstitial fluid, which is the liquid found in the spaces between cells, can also be present in small amounts in capillary samples.

Thus, the correct option reflects the complexity of capillary blood, capturing the fact that it is not solely arterial or venous but rather a blend that represents a more comprehensive context of the body's metabolic activity.