aTeväravoolusüsteemid

Atevavoolusüsteemid, also known as blood flow systems or circulatory systems, are biological networks responsible for the circulation of blood throughout an organism. These systems are vital for transporting oxygen, nutrients, hormones, and other essential substances to cells and tissues, while also removing waste products like carbon dioxide. The complexity and structure of these systems vary greatly across different species.

In simpler organisms, a tevavoolusüsteem might be an open circulatory system where blood, or a similar fluid called hemolymph, is pumped into open spaces within the body, bathing the organs directly. This is common in arthropods and most mollusks. In contrast, a closed circulatory system, found in vertebrates, annelids, and cephalopods, features blood contained within a continuous network of vessels. This allows for more efficient and directed transport.

The core components of most tevavoolusüsteemid include a heart or a similar contractile organ that acts as a pump, and a system of vessels such as arteries, veins, and capillaries. Arteries typically carry blood away from the heart, branching into smaller arterioles and then into capillaries, the tiny vessels where the exchange of gases and nutrients occurs with the surrounding tissues. Capillaries then merge into venules and finally into larger veins, which return blood to the heart. The continuous movement of blood ensures that all parts of the body receive the necessary resources for survival and function.