- Blood circulates through arteries, veins, and capillaries in a closed system.
- Tissue fluid fills the spaces between cells and facilitates exchange between blood and cells.
- Lymph is transported through lymph vessels and supports immune function.
- Arteries carry oxygenated blood (bright red), while veins carry deoxygenated blood (dark red), although veins may appear blue from the outside.
- Non-circulating fluids, like synovial fluid and vitreous humour, are confined to specific organs and do not move through a circulatory system.
Definitions [3]
Definition: Closed Blood Circulatory System
A closed blood circulatory system is one in which blood flows entirely within blood vessels, as seen in humans and other vertebrates.
Definition: Open Blood Circulatory System
An open blood circulatory system is found in animals like insects, where blood flows freely through body cavities without confined blood vessels.
Define portal vein.
A portal vein is one that starts with capillaries and also ends in capillaries.
Key Points
Key Points: Fluids in Our Body
