Trading Places
- Every organism must exchange materials and energy with its
environment, and this exchange ultimately occurs at the cellular
level.
- Most animals have organ systems specialized for exchanging
materials with the environment, and many have an internal transport
system that conveys fluid (blood or interstitial fluid) throughout the
body.
General Properties of Circulatory Systems
A circulatory system has
- A circulatory fluid
- A set of interconnecting vessels
- A muscular pump, the heart
The circulatory system connects the fluid that surrounds cells with the organs that exchange gases,
absorb nutrients, and dispose of wastes
Circulatory systems can be open or closed, and vary in the number of circuits in the body
2 Types of Circulatory System