Consists of : 1. Brain 2. Spinal Cord a. Protected by glial cells & meninges b. High metabolic rate that requires nutrients and oxygen c. Must be isolated from compounds in blood that could interfere with functioning

33 layers of specialized membranes surrounding brain & spinal cord AA) Dura Mater: 2 fibrous layers; outermost; very tough, holds brain in place CContains fluid, blood vessels & some adipose tissue PProvides stability & shock absorption to CNS tissue BB) Arachnoid: middle; small amt lymphatic fluid (reduces friction) & CSF CCerebrospinal Fluid (CSF): absorbs shock & transports gases, nutrients, chemical messengers, & wastes CC) Pia Mater: innermost; extensive circulatory supply due to high rate of metabolism MMeningitis: inflammation of meninges due to bacterial or viral infection

 Sends sensory info to brain & motor info from brain to rest of body  Spinal Reflexes: automatic responses controlled solely w/in spinal cord (i.e. withdraw from pain)  Central Canal: narrow central opening filled w/ CSF  Gray Matter: inside; contains neuron cell bodies & neuroglia…forms an H or butterfly shape  White Matter: outside; contains axons of neurons  Dorsal Roots: carry sensory info to spinal cord  Ventral Roots: carry motor info to muscles and glands

 31 segments designated by letter and number: C1  C8Cervical Vertebrae T1  T12Thoracic Vertebrae L1  L5Lumbar Vertebrae S1  S5Saccral Vertebrae CO1Coccygeal near tailbone Each segment has a dorsal root ganglia a. Dorsal Root- axons of sensory neuron b. Ventral Root- Axons of CNS motor neuron All spinal nerves are mixed because they contain sensory and motor neurons

““ Rostral ” = anterior (towards nose) “ Caudal ” = posterior (towards tail) 44 Major Parts: 11) C erebrum: divided into 2 hemispheres w/ 5 lobes CCorpus Callosum: thick bundles of nerves connecting 2 hemis. 22) C erebellum : inferior to cerebrum SSensory perception, motor output, motor control (heart, blood pressure, breathing, etc.) 33) B rain Stem : btwn cerebrum & foramen magnum AAttention, arousal, consciousness CComposed of midbrain, pons, and medulla oblongata 44) D iencephalon: inner core; btwn cerebral hemisph. ssensory processing, emotion, hormone production

1. Cerebrum- 2. Diencephalon (Hypothalamus to pituitary gland)- 3. Midbrain 4. Pons 5. Medulla Oblongata 6. Cerebellum

 83% brain volume  Gyri: thick folds  Sulci: shallow grooves that separate gyri  Central Sulcus: divides frontal/parietal lobes  Lateral Sulcus: distinguishes temporal lobe  Fissures: deep grooves throughout  Longitudinal Fissure: divides R/L hemispheres

11) F rontal: voluntary (skeletal) muscle control, motivation, memory 22) P arietal: sensory reception, taste, some vision 33) T emporal: hearing, s mell, learning, m emory, emotional behavior 44) O ccipital: main visual center 55) I nsula: deep inside; understanding speech, taste, sensory integration

MMost of cerebral volume TTransmits signals throughout cerebrum & to lower brain centers CContains axons of neurons

NNeural Integration CContains neuron cell bodies & neuroglia 11) C erebral Cortex: thin layer covering hemispheres SStellate Cells: receive sensory input & process local info PPyramidal Cells: transmit signals to other parts CNS 22) B asal Nuclei: deep masses w/in white matter RReceive & send signals to midbrain & motor cortex 33) L imbic System: includes amygdala & hippocampus IImportant for emotion & memory