So when the angle is decreasing and when I'm pulling my bones closer to my body, our bicep contracts, it's the agonist. While this, our tricep, is elongating, it's our antagonist. On the other hand, let's look at diagram B in which the opposite is taking place. So now I want to increase my angle between these bones and my joint hinge. And I basically want to move these two movable bones away from my body. And basically for this to actually take place, the electrical signal now must basically cause the contraction of the tricep muscle.