Week 2 - Normal Function of the Nervous System (Parts 1-4) PDF

**Study Questions** **Week 2 -- Normal Function of the Nervous System (parts 1-4)** **1) What is a homeostatic feedback system? What do they do? Describe an example of one. What body systems serve as the "control systems of the body" and therefore control most homeostatic feedback systems?** Home...

**Study Questions** **Week 2 -- Normal Function of the Nervous System (parts 1-4)** **1) What is a homeostatic feedback system? What do they do? Describe an example of one. What body systems serve as the "control systems of the body" and therefore control most homeostatic feedback systems?** Homeostatic feedback system - - - - - **2) Describe the structure of the Nervous system: Central vs. Peripheral, Afferent vs. Efferent. Etc.** CNS -- brain & spinal cord Peripheral -- nerves that branch from brain & spinal cord - - - - - - - - - **3) Describe the general structure of a neuronal cell. What is myelination?** Neuronal cell - - - - - - - - - - - - - - **4) Compare and contrast the three basic types of neuronal cells: afferent, efferent, & interneuron.** Efferent neurons - - Afferent neurons - - - Interneuron - - **5) Define and explain equilibrium potential. In what direction will an ion move when a cell is at that ion's equilibrium potential? Why?** Membrane potential = separation of charge & permeability across membrane - - K+ equilibrium potential = -90 mV - - Na+ equilibrium potential = +60 - **6) What factors determine resting membrane potential?** Resting membrane potential= -86 mV - - - - - - **7) Review the changes in membrane potential that occur during an action potential. What are the underlying events involved?** **8) What purpose does the myelin sheath serve?** increases conduction speed of AP down axon, prevents loss of signal **9) What is a synapse? What types of synapses exist?** Synapse - - - - - - - - - - **10) What are the steps involved in synaptic transmission at a chemical synapse?** Steps of chemical synaptic transmission 1. 2. 3. 4. 5. 6. 7. **11) What is the difference between a neurotransmitter and a neuroactive peptide?** Neurotransmitter - - - - - - - - - - - - - - - Neuroactive peptides - - - - **12) Describe, compare, and contrast the following categories of neurotransmitters: Amino acid, monoamines, and catecholamines.** **13) What are the predominant excitatory and inhibitory neurotransmitters found in the central nervous system?** - - - **Case Study** Jean was a 54-year old woman recently hospitalized and diagnosed with congestive heart failure. Upon discharge from the hospital, she was given a prescription for Lasix (furosemide) 20 mg p.o. daily. After 1 week at home she had lost 3 pounds of water weight. She was very excited about this weight loss and decided "*If 1 pill is good, 2 pills are better*" and so she began to take 40 mg of furosemide daily. A week later she presents to the emergency room with generalized weakness, leg cramps, constipation, and "strong" heartbeats. 1\. What was the likely cause of Jean's symptoms? Hypokalemia K+ AP of neurons & muscle cells: repolarization Loss of extracellular K+ causes K+ to leave cell through leak channels - Musculoskeletal: muscle cells are firing rapid consecutive APs → cramping GI: constipation r/t dehydration - -