Each cerebral hemisphere is divided into four lobes; the frontal, parietal, temporal, and the occipital. The Frontal Lobe is the most anterior lobe of the brain.Its posterior boundary is the fissure of Rolando, or central sulcus, which separates it from the parietal lobe.Inferiorly, it is divided from the temporal lobe by the fissure of Sylvius which is also called the lateral fissure.he Frontal Lobe is the most anterior lobe of the brain. Its posterior boundary is the fissure of Rolando, or central sulcus, which separates it from the parietal lobe. Inferiorly, it is divided from the temporal lobe by the fissure of Sylvius which is also called the lateral fissure.
Main article: Thoracic diaphragm. The diaphragm is the major muscle responsible for breathing. It is a thin, dome-shaped muscle that separates the abdominal cavity from the thoracic cavity. During inhalation, the diaphragm contracts, so that its centre moves caudally (downward) and its edges move rostrally (upward).
Physiology. Your intercostal muscles are located between your ribs. These muscles expand and contract to move your ribs, giving your lungs enough room to inhale and exhale. You have three layers of these important respiratory muscles â the external, innermost and internal intercostal muscle layers.hysiology. Your intercostal muscles are located between your ribs. These muscles expand and contract to move your ribs, giving your lungs enough room to inhale and exhale. You have three layers of these important respiratory muscles â the external, innermost and internal intercostal muscle layers.