system
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human
My MCAT bio book says that glucagon stimulates glycogenolysis and gluconeogenesis in the liver. Why does it stimulate two seemingly opposing processes?

First off, I apologize for the poorly worded question. I know the overall result of glucagon is to increase blood glucose levels, but what I don't understand is how it accomplishes this by stimulating both glycogenolysis (the breakdown glycogen to glucose) and gluconeogenesis (creation of glucose and **GLYCOGEN**). Wouldn't gluconeogenesis just counteract the glycogenolysis and accomplish nothing? Or am I missing something?
gpt
Your MCAT bio book is correct. 

Glucagon is released to maintain adequate blood glucose levels.

Glycogenolysis is stimulated to break down glycogen into glucose (as you said). Gluconeogenesis is not the same thing as glycogen synthesis (glycogenesis - the creation of glycogen). We can make glucose out of pyruvate or other metabolic intermediates in order to maintain adequate blood glucose levels. 

So gluconeogenesis and glycogenolysis are not two counteracting pathways - they result in the same thing, which is an increase of glucose in our bloodstream. 

BTW: these two processes (glycogenolysis and gluconeogenesis) are happening primarily in the liver. Those newly synthesized glucose molecules are then released from the liver and into the bloodstream.