1. The Nervous System

2. The Nervous System: Chief control system; voluntary or involuntary Responds to changes in/out of body 100 Billion cells throughout the body CNS: brain and spinal cord act as a switching center for impulses Peripheral nerves: a cable system

4. A) Neurons: Anatomy 1) Cell body (CB): branches send or receive nerve impulses (NI) 2) Dendrites: thin extensions of cell body; conduct NI back toward CB 3) Axon: conduct NI away from CB Myelin sheath: fatty tissue, covers axon

5. A) Neurons: Physiology: Synapse: impulses jump over space bet. neurons Neurotransmitters: substances located at end of nerve fibers

6. Anatomy Of A Synapse:

7. A) Neurons: Properties: 1) excitability: ability to respond to stimulus 2) conductivity: ability to transmit signal

8. A) Neurons: 3 Types: 1) Efferent: “exiting” (motor) neurons; send info to muscles/glands of CNS 2) Afferent: “returning” (sensory) neurons; carry info from sensory receptors back to CNS 3) Interneurons: “between” (connecting) process sensory information

10. Monosynaptic Reflex Arc:

11. A) Neurons: Impulses Form bundles called “nerves” that bear electrical messages Some nerves are combinations of at least two types of nerves Electrical E stored; then released when cells receive outside or internal chemical stimulus Released E travels through nerve cell causing an impulse, then transmitted to other receptors in the body

12. B) Neuroglias: Function to support, connect, protect, remove debris Do not transmit impulses “Brain Blood Barrier” found along the capillary walls of the brain: allows some chemical substances to reach brain, but blocks others

13. B) Neuroglias:

14. C) The CNS: Anatomy: Brain and spinal cord; control center Receives/interprets all stimuli; sends NI to muscles and glands Voluntary control, involuntary movement; seeing, hearing, thinking, secretion of hormones, memory, responding to outside stimuli

15. C) Anatomy:

16. C) The CNS: Four Parts 1) Brainstem: a) Midbrain: visual reflexes b) Pons: respiration c) Medulla oblongata: heart, lungs, swallowing, vomiting, coughing, sneezing 2) Cerebellum: musculoskeletal movements; posture, balance, muscle tone

17. C) The CNS: Four Parts 3) Cerebrum: L/R hemispheres; outer covering cerebral cortex: conscious decision-making Four Lobes: a) frontal: voluntary mvts, emotions, morality b) parietal: senses, taste c) temporal: memory, equilibrium, emotion, hearing d) occipital: vision, expression

18. C) The CNS: Four Parts 4) Diencephalon: deep portion, thalamus and hypothalamus Relay center for sensations Integrates Autonomic Nervous System (ANS): heart rate, BP, Temp. regulation, H20/electrolyte balance, digestion, behavior, glands

19. C) The CNS:

20. C) CNS: Cerebrospinal Fluid: Watery fluid flows throughout the brain, surrounds spinal cord Cradles, cushions, protects brain Spinal Cord: Fills space in vertebral canal (SC housed) Spinal Meninges: protect SC, surrounded by CSF

21. Meninges:

22. C) CNS: Spinal Meninges 1) Dura Mater: outermost; a tough, fibrous membrane covering entire length of SC with channels for blood to enter brain 2) Arachnoid Mater: middle; weblike structure across the space containing CSF 3) Pia Mater: innermost; thin membrane containing BV that nourish the SC *Epidural space: between dura mater and vertebrae; injections given here

24. D) Peripheral Nervous System (PNS) 12 pairs of cranial nerves; carry impulses to and from the brain 31 pairs of spinal nerves; carry messages to and from the spinal cord/torso to extremities Divided into two subsystems according to function: A) Somatic Nervous System B) Autonomic Nervous System

27. D) Peripheral Nervous System (PNS) 1) Somatic Nervous System: a) receive/process sensory input; from skin, muscles, tendons, joints, eyes, tongue, nose, ears b) voluntary contraction of skeletal muscle

28. D) Peripheral Nervous System (PNS) 2) Autonomic Nervous System: from CNS to glands; cardiac, various membranes; secretions a) Sympathetic: reacts to stress with the “fight or flight” response b) Parasympathetic: maintains homeostasis

29. E) Diseases and Disorders: ConcussionMultiple Sclerosis ContusionMyasthenia Gravis Spina BifidaParkinson’s HydrocephalusEpilepsy Cerebral PalsyTourette’s Alzheimer’sParalysis Amyotrophic Lateral Sclerosis (ALS)

30. D/D: Concussion: A) Coup

31. D/D: Concussion: B) Contre Coup

32. D/D: Contusion

33. D/D: Hematomas

34. D/D:Craniotomy

35. D/D: Bell’s Palsy

36. D/D: Parkinson’s