The blood circulates, so blood is reused constantly. There's no break in the circle, so it is a closed system
Answer:
Air
Explanation:
Because of the trees, we breath.
Hey there!
Carbon is the key element found in co2 and glucose.
Hope this helps!
Have a great day! (:
The division of the peripheral nervous system where it is responsible for producing physiological symptoms (such as increased heart rate and butterflies in the stomach) under conditions of stress would be the sympathetic division. It is also called the emergency system since it prepares the body for any physical activity that would be intense.
