The organism that you described is most likely a star fish. All its limbs go from the middle and if one is damaged or removed, a new one will grow from the center to replace it.
The atrioventricular valves.
Answer:
Gas exchange
Explanation:
Gas exchange takes place in the millions of alveoli in the lungs and the capillaries that envelop them. As shown below, inhaled oxygen moves from the alveoli to the blood in the capillaries, and carbon dioxide moves from the blood in the capillaries to the air in the alveoli.
