Plants use carbon to live, just like humans use oxygen. It's a virtuous cycle sine humans breathe oxygen and expel carbon, and plants "breathe" carbon and expel oxygen.
If plants weren't there to "breathe" the carbon, it would just sit in the world, and build up in the atmosphere.
Pond organisms live in shallow water so they can produce
Answer:
It is secreted by the pancreas
Explanation:
Insulin is used for negative feedback of blood sugar levels in the blood. It promoted uptake of glucose by cells when the blood sugars are high, especially after a meal. Glucagon hormone, on the other hand, is responsible for the positive feedback.