Final answer:
The statement is false. There is a series of events that occur before the muscles start pulling on the bone.
Step-by-step explanation:
The statement "there is no delay when your muscle contracts resulting in immediate pull on the bone" is False. When a muscle contracts, there is a series of events that occur before the muscle fibers actually start pulling on the bone. This process includes the release of neurotransmitters, calcium ions, and the formation of actin-myosin cross-bridges.
First, a motor neuron stimulates the muscle fiber to release neurotransmitters, such as acetylcholine, which initiates the contraction process. The neurotransmitters bind to receptors on the muscle fiber and trigger the release of calcium ions from the sarcoplasmic reticulum. The calcium ions then bind to troponin, causing tropomyosin to move away from the binding sites on actin.
Once the binding sites on actin are exposed, myosin heads can attach to them, forming cross-bridges. The myosin heads then undergo a power stroke, pulling the actin filaments towards the center of the sarcomere. This sliding of the thin filaments over the thick filaments results in sarcomere shortening and muscle contraction. Only after these processes occur, the muscle fibers start pulling on the bone, generating tension and movement.