Explained: Cardiovascular centers and Rhythmicity area of Medulla скачать в хорошем качестве

Explained: Cardiovascular centers and Rhythmicity area of Medulla

You can download the content of video from below link. https://www.slideshare.net/secret/JyW... Mudulla contains cardiovascular centers and respiratory rhythmicity area. Cardiovascular centers control blood pressure, diameter of blood vessels, and rate and force of heart beat. When baroreceptors, present in arch of arota and carotid sinus are stimulated due to stretch of arch of arota and carotid sinus, the baroreceptor will send impulses to cardiac center of medulla. This impulses travel to cardiovascular center by cranial nerve number IX (Glassophyrengial nerve) and X (Vagus Nerve). In response, cardiovascular centers of medulla, sends parasympathetic impulses to SA node and AV node by vagus nerve. Hence, due to parasympathetic stimulation of heart, the heart rate decreases. Additionally cardiovascular centers of medulla also sends impulses to spinal cord and by that decreases stroke volume and heart rate. The chemoreceptor center of medulla sends impulses to spinal cord and causes blood vessel dilation. So, decrease in heart rate, stroke volume and dilation of blood vessels causes decrease in blood pressure. In reverse, when the blood pressure increases, barorecpetors sends impulses to cardiovascular centers. In response, cardiovascular centers releases sympathetic outflow and increases blood pressure. Another are is rhymicity area. Medulla contains rhythmicity. Under this area, there is dorsal respiratory group and Ventral respiratory group. In Ventral Respiratory group, there is inspiratory area and expiatory area. Inspiratory area sends impulses to external intercostal muscles via intercostal nerve and diaphragm via phrenic nerve. Causes quiet inspiration for 2 seconds. The impulses stop after 2 seconds and then begins expiration for about 3 seconds. During forceful breathing, inspiratory area excites expiatory area. Expiatory area sends impulses to internal intercostal muscles and other accessory respiratory muscles. Leading to forced exhalation.