Describe What Happens When a Muscle Contracts.
The actin and myosin cross bridges bind and contract using ATP as energy ATP is an energy compound that all cells use to fuel their activity this is discussed in greater detail in the energy system folder here at ptdirect. A skeletal muscle contraction is the mechanism by which muscles of the movable joints of the body produce movement at those joints. Myofibrils Micrograph Plasma Membrane Muscle Pelvic Floor This repeated movement is. . Describe what happens when a muscle contracts. An action potential in a motor neuron causes acetylcholine to release in the synaptic cleft. 2 A motor neuron in the ventral horn of the spinal cord is activated and an action potential passes outward in a ventral root of the spinal. This results in shortening of the sarcomere. During muscle contraction the actin filament is pulled along myosin toward the centre of the sarcomere until the actin and myosin filaments are completely overlapped. S...