How can the circulatory system be described?Multiple choice question.a mixed system (contains one open and one closed circuit)a closed systeman open system

The circulatory system can be described primarily as a closed system in humans and many other vertebrates. Here’s a brief explanation for each option:

1. A Mixed System (Contains One Open and One Closed Circuit): This description could apply to some organisms, but it is not accurate for mammals. Humans possess a closed circulatory system.

2. A Closed System: This is the correct description for the human circulatory system. In a closed circulatory system, blood is contained within vessels and does not leave the network, circulating through arteries, veins, and capillaries. The heart pumps the blood throughout the body, maintaining a high level of pressure and ensuring efficient transport of nutrients, gases, and wastes.

3. An Open System: This refers to systems where blood is not always contained in vessels and is instead allowed to flow freely in body cavities. This type is characteristic of invertebrates, such as insects and some mollusks, and does not apply to humans.

Based on this analysis, the correct choice for the human circulatory system is: a closed system.