So if a woman is about to give birth, so that uterus must contract. And it's these gap junctions that allows the contraction of that uterus muscle. Now, another area that uses gap junctions to basically communicate between nearby cells is inside the brain. So inside the brain, certain types of nerve cells don't actually use neurotransmitters to send action potential from one cell to another. Instead of using your transmitters, they actually use gap junctions. So on the presynaptic cell and the post synaptic cell, they're connected by these gap junctions.