Chapter 7 The Nervous System Notes PDF

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Name: Kaitlynn Stubbs Chapter 7 The Nervous System Notes (Page 1) I. Organization A. Structural Classification 1. Central Nervous System (CNS) a. brain & spinal cord b. Receive, interpret & give instructions. 2. Peripheral Nervous System a. The part of the nervous system outside the CNS. b. Consists of nerves that extend from the spinal cord and brain. B. Functional Classification 1. Sensory Division – Impulses from body to CNS. 2. Motor Division – Impulses from CNS to body. a. Somatic – Voluntary actions (control muscles). b. Autonomic – Involuntary actions (heart, stomach, glands). II. Structure of Nervous System A. Supporting Cells 1. Neuroglia a. “Nerve glue,” holds, insulates, and protects neurons. b. cannot transmit impulses B. Neurons – Nerve cells that transmit messages. a. Cell Body – Contains nucleus (main part). b. Process of Fibers – Long-arm like extension. 1. Dendrite – Towards cell body (small). 2. Axon – Away from cell body (large). c. Myelin – Fatty material that insulates neurons and helps conduct impulses. d. Neurotransmitters – Chemicals released to transmit signals between neurons. e. Synapse – Junction between two neurons. f. Ganglia – Collections of cell bodies. g. White Matter – Collections of myelinated fibers. h. Gray Matter – Collections of unmyelinated fibers and cell bodies. 2. Nerve impulse conduction  Sodium (Na+) and Potassium (K) are important in generating impulses in the body. 3. Reflexes – Rapid, predictable and involuntary responses to stimuli. III. Central Nervous System A. Cerebral Hemispheres 1. Gyri – Elevated ridges of tissue. 2. Sulci – Shallow grooves in the brain. 3. Fissure – Deep grooves in the brain that usually divides into 2 parts. 4. Cerebral Cortex – Outermost layer of the brain made up of gray matter. 5. Lobes – Sections of the brain. a. Frontal, b. Parietal, c. Occipital, d. Temporal

Name: Kaitlynn Stubbs Chapter 7 The Nervous System Notes (Page 2) Other Parts of the Cerebrum: Hippocampus: (horn-shaped) Location = Inside medial temporal lobe surrounding the diencephalon. Function = Forming memories and emotions (limbic system) Amygdala: (almond-shaped) Location = temporal lobe Function = Associated with emotional memories (e.g. fear) and aggression (limbic system). **Corpus Callosum: Area of white matter deep in the brain that connects the 2 hemispheres. B. Diencephalon – Above the brainstem, between the cerebral hemispheres. 1. Thalamus – Produces sensations of arousal or alertness. 2. Hypothalamus – Regulates body temperature, metabolism, pituitary gland, pleasure, fear and anger. C. Brainstem – Area between brain and spinal cord. 1. Mid-brain: Relay motor and sensory impulses (brain to spinal cord). Contains interneurons for visual and auditory reflexes. 2. Pons: Made up of large motor and sensory tracts. The pons relays signals to the cerebellum, and deals primarily with BREATHING, sleep, swallowing, bladder control, hearing, equilibrium, taste, eye movement, facial expressions, facial sensation, and posture. 3. Medulla Oblongata: Most inferior part of brain stem. Regulates heart rate, blood pressure, breathing, swallowing, vomiting, coughing and sneezing....