1. Lesson 6.1 Overview of the Nervous System Chapter 6: The Nervous System

2. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. two major divisions –central nervous system (CNS) Brain & spinal cord –peripheral nervous system (PNS) sensory receptors –Responds to stimuli from pain, pressure & temperature afferent (sensory) nerves –Impulses from receptors in skin, muscles or joints to the CNS efferent (motor) nerves –Impulses from CNS to muscles & glands Organization of the Nervous System

3. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Two Major Divisions If you had to add the word VOLUNTARY to one of the boxes above, which would it be?

4. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. somatic nervous system –Voluntary –Stimulates skeletal muscles autonomic nervous system –involuntary –Sympathetic Controls fight-or-flight response –Parasympathetic Controls automatic everyday functions of circulatory, respiratory & digestive systems Also controls involuntary muscles The Efferent Nerves

5. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. neuroglia –also known as glial cells –support the neurons –protect the neurons neurons –transmit nerve impulses Nerve impulses are electrical charges that travel along the nerve fiber when stimulated Nervous Tissues

6. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. central nervous system 4 types of neuroglia –Astrocytes Links capillaries to neuron Protects neuron from harmful things in blood –Microglia Dispose of dead cells & bacteria –Ependymal Protective covering around spinal cord & brain –oligodendrocytes Produces fatty insulation around nerve fibers called myelin Neuroglia

7. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. peripheral nervous system –Schwann cells Forms fatty myelin sheath around PNS nerve fiber Non-myelinated axon sections are nodes of Ranvier –satellite cells Cushioning support Neuroglia

8. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. dendrites –Collects stimuli & sends information to cell body cell bodies –Includes nucleus & mitochondria axons –send information away from cell body Parts of a Neuron

9. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Myelin sheaths are white –White matter is tracts of myelinated fibers within the CNS. Gray matter is the term for unmyelinated nerve fibers. Neurons

10. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. sensory neurons –send impulses toward CNS motor neurons –send impulses away from CNS interneurons –bridges between neurons –also called association neurons –Intersection between 2 nerves is called a synapse Reflexes are simple, rapid, programmed responses to stimuli Neuron Types by Function

11. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. bipolar –one axon and one dendrite Neuron Structures multipolar –one axon and many dendrites unipolar –one axon

12. Lesson 6.3 Functional Anatomy of the Central Nervous System Chapter 6: The Nervous System

13. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. cerebral cortex –Gyrus Raised convolution on brain surface –Sulcus Groove between sulcus –fissure Uniformly positioned, deep groves in brain Cerebrum Cerebrum is largest part of brain – has left & right hemispheres.

14. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Cerebral Gyri

15. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. lobes –Frontal Memory, intelligence & emotions –parietal –occipital –temporal primary motor cortex primary somatic sensory cortex Cerebrum

16. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Cerebrum

17. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. thalamus Hypothalamus –Centers for sex, pain, & pleasure epithalamus Diencephalon

18. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. 1. midbrain 2. Pons –Regulates some breathing 3. medulla oblongata –Regulates heart rate, blood pressure, breathing and controls reflexes for coughing, sneezing, & vomiting Brain Stem

19. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Cerebellum –Coordinates body movements & balance blood-brain barrier The Brain

20. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. The Brain Meninges 3 protective membranes surrounding brain & spinal cord –dura mater –Outer layer –arachnoid mater –Middle layer –pia mater –Innermost layer

21. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Spinal Cord Spinal nerves are neural transmitters that branch from the left & right sides of spinal cord.

22. Lesson 6.4 Functional Anatomy of the Peripheral Nervous System Chapter 6: The Nervous System

23. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. endoneurium –covers axons perineurium –bundles fascicles epineurium –wraps nerves Nerve Structure

24. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. 31 pairs dorsal root ventral root dorsal ramus ventral ramus Plexuses –Complex interconnections of nerves Spinal Nerves and Nerve Plexuses

25. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. preganglionic and postganglionic neurons sympathetic nerves –fight-or-flight action parasympathetic nerves –resting or digesting action Autonomic Nervous System

26. Lesson 6.5 Injuries and Disorders of the Nervous System Chapter 6: The Nervous System

27. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. violent impact to head –Mild Headache, fatigue, & bad taste in mouth –moderate –severe Traumatic Brain Injury

28. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. damage to brain –before birth –during birth –during infancy motor function impairment Cerebral Palsy

29. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. C1–C3: usually fatal C1–C4: quadriplegia –Trunks & all 4 limbs are paralyzed C5–C7: paralysis of lower extremities T1–L5: paraplegia Trunk & 2 limbs are paralyzed Spinal Cord Injuries Corepics/Shutterstock.com

30. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Meningitis –Head & neck pain, fever multiple sclerosis –Destroys the myelin sheath Epilepsy –Seisures Parkinson’s disease –tremors dementia and Alzheimer’s disease –Loss of mental capacity Common Diseases and Disorders of the CNS