Describe the actions of the biceps and triceps muscles when straightening the forearm. State one feature of the elbow joint and explain the type of movement it allows. Identify where an infection woul

26. (a) To straighten the forearm:
Muscle X (triceps) contracts, while Muscle Y (biceps) relaxes. The contraction of the triceps pulls on the ulna, causing the forearm to extend or straighten.

26. (b)
One feature of joint T (the elbow joint) is that it is a hinge joint, allowing movement in one plane only.

27. (a)
The infection is located in the large intestine (colon).

27. (b)
The structure that secretes digestive enzymes and bicarbonate ions is the pancreas.