Final answer:
A complex movement consists of isometric and isotonic movements. A circular movement at a condyloid joint is known as circumduction. Biceps contraction causes flexion, likely through isotonic contraction, and triceps contraction causes extension of the elbow joint.
Step-by-step explanation:
A complex movement typically consists of two types of movements: isometric and isotonic. Isometric movements involve muscle contraction without changing the muscle length or moving the joint. An example of this would be pushing against a wall. Isotonic movements, on the other hand, involve muscle contraction with changes in the muscle length and joint movement, such as lifting a weight in a bicep curl.
As for the question about the type of motion produced by a circular movement at a condyloid joint, the correct answer is circular motion or circumduction, which is not explicitly stated in the initial options given. Circumduction involves moving a body part, such as the arm, in a circular manner involving flexion, extension, abduction, and adduction.
If the biceps contract and the arm moves, this creates flexion of the elbow joint. This movement is most likely an isotonic contraction because the muscle changes length, causing the arm to move. Finally, if the triceps were to contract, it would produce extension of the elbow joint, causing the arm to straighten out.