Which muscle relaxes to allow the elbow to flex?

Which of the following muscles inserts into the posterior calcaneus via the calcaneal tendon?

Which muscle relaxes to allow the elbow to extend?

Which of the following muscles extends the knee?

Which of the following is an example of antagonistic muscle action?

What structure attaches a muscle to a bone?

Which muscle is responsible for the rotation of the scapula and depression of the shoulder?

Which of the following muscles does not flex the forearm?