1. The document compares the nervous systems of invertebrates and vertebrates, noting that invertebrates have a nerve net while vertebrates have a central nervous system consisting of the brain and spinal cord, as well as a peripheral nervous system.
2. The vertebrate nervous system includes reflex responses controlled by the spinal cord without brain involvement, as well as afferent and efferent neurons that transmit sensory and motor signals.
3. The brain is regionally specialized with areas controlling functions like homeostasis, movement coordination, language, and emotions.
4. Figure 49.4 Central nervous system (CNS) Brain Spinal cord Peripheral nervous system (PNS) Cranial nerves Ganglia outside CNS Spinal nerves
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7. Parasympathetic division Action on target organs: Constricts pupil of eye Stimulates salivary gland secretion Constricts bronchi in lungs Slows heart Stimulates activity of stomach and intestines Stimulates activity of pancreas Stimulates gallbladder Promotes emptying of bladder Promotes erection of genitalia Cervical Thoracic Lumbar Synapse Sacral Sympathetic ganglia Sympathetic division Action on target organs: Dilates pupil of eye Accelerates heart Inhibits salivary gland secretion Relaxes bronchi in lungs Inhibits activity of stomach and intestines Inhibits activity of pancreas Stimulates glucose release from liver; inhibits gallbladder Stimulates adrenal medulla Inhibits emptying of bladder Promotes ejaculation and vaginal contractions Figure 49.8
8. Regions of the Brain Figure 49.UN04 Spinal cord Cerebral cortex Cerebellum Medulla oblongata Pons Hindbrain Midbrain Forebrain Cerebrum Thalamus Hypothalamus Pituitary gland
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11. Changes in Synaptic Connections Figure 49.19 N 2 N 1 N 2 N 1 (a) Synapses are strengthened or weakened in response to activity. (b) If two synapses are often active at the same time, the strength of the postsynaptic response may increase at both synapses.
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13. Drug Addiction and Brain Reward System Figure 49.23 Nicotine stimulates dopamine- releasing VTA neuron. Inhibitory neuron Dopamine- releasing VTA neuron Cerebral neuron of reward pathway Opium and heroin decrease activity of inhibitory neuron. Cocaine and amphetamines block removal of dopamine from synaptic cleft. Reward system response
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