protective membranes covering the brain. meninges: dura mater, arachnoid, and pia mater. cross section of the human brain. layers

anatomy arachnoid bacteria biology blood body bone brain care central cerebral cerebrospinal cord cortex cross diagram disease dura fluid head health human illustration infection inflammation layers lobe mater matter medical medicine meninges meningitis mental nervous neurology organ periosteum pia render sagittal science section sinus skull space spinal subarachnoid system tissue