Muscle Contraction Essay

Muscle contractions tend to be smooth and vary in strengths, depending on the demands placed on them. The variations of strength are called graded muscle responses. There are two ways a muscle contraction can be graded, either by changing the frequency of stimulation or by changing the strength of the stimulation. When a muscle is responding to a change in stimulus frequency, the nervous system will reach a greater muscular force when increasing the firing of motor neurons. This causes a wave or temporal summation, which is when the second twitch of the muscle is stronger than the first. This occurs because the second contraction occurs before the muscle has completely relaxed and more Ca2+ is still being released, which causes more shortening
ATP is the source of energy for the sliding. They both experience an increase in calcium for muscle contraction, and a decrease when the muscle relaxes. The cross-bridge attachments form and break multiple times during a contraction to help create more tension.
The digestive system creates and ideal environment for the functioning of the GI tract. The GI tract initiates the digestive system by triggering mechanical and chemical stimuli that can be detected by chemoreceptors and mechanoreceptors. The activation of the digestive system can be either extrinsic or intrinsic; nervous or hormonal. The enteric nervous system is responsible for the short and long reflexes of the digestive system. The short reflexes control smooth muscle contractions and glandular secretions of the digestive tract. Long reflexes have to do with interneurons and motor neurons in the central nervous system. These provide more control over the digestive and glandular activates. Hormonal process’ involve about 18 hormones, each affecting digestive functioning. Local mechanisms involve prostaglandins, histmins, and other chemicals that are released into the interstitial