Human body of different cavities, separated areas which house different organ systems. The brain and central nervous system reside in an area protected from the rest of the body by the blood brain barrier. The lungs sit in the pleural cavity. The intestines, liver, and spleen sit in the abdominal cavity Height, weight, shape and other body proportions vary individually and with age and sex. Body shape is influenced by the distribution of muscle and fat tissue. Human physiology is the study of how the human body functions. This includes the mechanical, physical, bioelectrical, and biochemical functions of humans in good health,
Precentral gyrus contralateral side of the body (facial palsy, arm-/leg monoparesis, hemiparesis) - see upper motor neuron. Precentral gyrus The precentral gyrus (also known as the motor strip) is a prominent structure on the surface of the posterior frontal lobe. It is the site of the primary motor cortex (Brodmann area 4). The precentral gyrus lies in front of the postcentral gyrus - mostly on the lateral (convex) side of each cerebral hemisphere - from which it is separated by the central sulcus. Its anterior border is represented by the precentral sulcus, while inferiorly it borders to the lateral fissure ("Sylvian fissure").