Why makes our stomachs grumble..?

Question

and make noises when it's hungry?

Answer 1

Our stomach grumbles when the acid juice churns the bolus (chewed food); so this allows the intestines to absorb nutrition and other vitamins much more easily. Or other explanations maybe that you are hungry and your stomach needs to digest, therefore it causes a grumbling noises. Also there are times when there is gas in your stomach and that sometimes cause noises as well.  

Answer 2

What makes our stomachs grumble..?

Noise.

Why does it make noises when it's hungry?

Because it grumbles.

Answer 3

Acids and juices flowing and mixing with no food.