The Nervous System

1. The Nervous System BY: Michelle May Stefanie Frayne

2. Job of the Nervous System • Maintaining internal environment • To monitor and respond to the external environment • Three Functions • Receive sensory input from environment • Integrate input • Respond to stimuli

3. Neurons • The basic unit of the nervous system • Also called a nerve cell • A typical neuron consists of: • The soma • Nerve fibers

4. The Soma Also called cell body Contains the nucleus and cell fibers Nerve Fibers Two Kinds: Axons: carry information away from the cell body Dendrites: carry information toward the cell body * Neurons have 1 axon and several dendrites Parts of the neuron

5. Central Nervous System Peripheral Nervous System Two Systems

6. The Peripheral Nervous System • Contains only nerves and connects the brain and spinal cord to the rest of the body. • Two types of Neurons in the PNS: • Motor Neuron: • Carries input from the central nervous system(CNS) to muscles and glands • Typically have one axon that goes from the spinal cord to the muscle or gland • Sensory Neuron: • Carries input from the sense organs to the CNS • Typically have long dendrites that carry the information from organ to the CNS

7. The Central Nervous System • Consists of the brain and the spinal cord • Surrounded by the skull and vertebrae of the spinal cord • Receives input from sense organs, interprets information, and creates responses

8. The Brain • Composed of Three Major Parts • Cerebrum • Cerebellum • Medulla Oblongata

9. Cerebrum & Cerebellum • Cerebrum • Largest part of the Brain • Controls Intelligence and reasoning • Learning and Memory • Cerebellum • Second Largest part of the brain • Body movement • Fine motor coordination • Posture • Balance

10. Medulla Oblongata • Closes to the Spinal Cord • Involved with • Regulates Heartbeat • Breathing • Blood Pressure • Reflex Centers • (Coughing, Sneezing etc.)

11. Unconscious areas of the Brain • Hypothalamus • Regulates • homeostasis • thirst • hunger • Body Temperature • Water Balance • Links Nervous System to the Endocrine System

12. Unconscious Areas of the Brain • Midbrain • Pons • Cerebellum • Thalamus • Serves as a central relay point for incoming nervous messages

13. Conscious Areas of the Brain • Corpus Callosum • Separates cerebral hemispheres • Cerebrum • Intelligence and reasoning • Learning and memory

14. Conscious and Unconscious areas of the Brain .

15. The Brain Stem & Midbrain • Brain Stem • Smallest and oldest part of the brain • Continuous with the spinal cord • Composed of: • Hindbrain • Midbrain • Midbrain • Connections between the hindbrain and forebrain • Ex. Eye Reflexes

16. Forebrain • Consists of : • Diencephalon • Thalamus and Hypothalamus • Cerebrum • Left and Right Hemispheres • Divided into four lobes • Occipital • Temporal • Parietal • Frontal

17. Temporal & Occipital • Temporal • Receives Auditory Signals • Processes language and meaning of words • Occipital • Back of head • Receives and processes visual Information

18. Parietal & Frontal • Parietal • Associated with Sensory Cortex • Processes Information about • Touch, taste, pressure, pain, heat and cold • Frontal • Three Functions • Motor Activity • Speech • Thought Process

19. The Spinal Cord • Runs along the dorsal side of the body • Links the brain to the rest of the body • Gray matter consists of cell bodies and dendrites • White matter consists of bundles of interneuronal axons • Involved in reflexes that do not immediately involve the brain

20. Disease of the Nervous System • Alzheimer’s Disease • Occurs in the brain • Physical illness • Form of Dementia • Affects a person’s memory, mood, and behavior • Affects neurons • Associated with protein plaques in the brain • Approximately 100,000 victims die and 360,000 new cases of this disease are diagnosed each year

21. Symptoms of Alzheimer’s • Cognitive • Memory loss • Disorientation • Confusion • Differences with thought reasoning • Behavioral • Agitation/anxiety • Delusion/ Hallucinations • Depression • Insomnia

23. Study Guide • Know the three functions of the nervous system • What is a neuron? • List the parts of a neuron • List the two kinds of nerve fibers & know what they do • Know the 2 main parts of the Nervous System (CNS & PNS)

24. Study Guide (cont’d) • List the 2 types of neurons in the PNS • Know the function of the PNS neurons • Know the difference between the CNS and the PNS • List the 3 main parts of the brain & know the job of each • Know the unconscious and conscious parts of the brain

25. Study Guide (cont’d) • Know the job of the brain stem, midbrain, and forebrain • Know the 4 lobes of the brain and describe function of each • Know the job of the spinal cord • Name a specific disease of the nervous system and list symptoms

26. Works Cited • Information: • “Alzheimer’s Disease Information Basics: What is Alzheimer’s Disease?” 24 April 2005. http://www.alzheimersdisease.com 2005 • “Alzheimer’s Disease: What is Alzheimer’s Disease?” University of Maryland Medicine. 22 April 2005. http://www.umm.edu/nervous/alzheim.htm 2005\ • “The Nervous System.” 23 Apr 2005. http://www.emc.maricopa.edu • Tillery, B., Enger, L., Ross, L.C. Integrated Science: Second Edition. McGraw Hill: New York. 2004. Pgs. 547-549. • Pictures: • Google Images