PHYSIOLOGY TUTORIAL

PHSL - 215

Graded Potential & Action Potential

Neuron

Nerve Conduction in Myelinated &

Unmyelinated Nerve Fiber

Synapse

Neuromuscular Junction

Topics

Q.1 What is graded potential?

Q2. What is action potential?

Q3. Give 4 differences between graded

potential & action potential

Q4. Draw diagram of AP of Neuron. Show

depolarization, repolarization and hyper

polarization phase and give the cause of each

phase.

Q5. Nerve fiber can be stimulated easily,

when it is at RMP or at hyper polarization

stage. Give reason for your answer.

Q6. What is absolute refractory period?

Q7. What is relative refractory period? 

Q8. Draw AP and show absolute and relative

refractory period? 

Q.9. Draw and label the parts of neuron

Q10. Where AP is generated in neuron?

Q11. What are the differences between

contiguous conduction and saltatory

conduction?

Q12. What is myelin sheath?  

Q13. What is node of Ranvier?  

Q14. What factors affect nerve conduction?  

Q15. What is synapse?

Q16. Draw the diagram of chemical synapse

 

Q17. What is excitatory post synaptic potential (EPSP)

Q18. What is inhibitory post synaptic potential (IPSP)  

Q19. What is neuromuscular junction?  

Q20. What is a neurotransmitter at neuromuscular

junction?  

Q21. How acetylcholine is destroyed?  

Q22. What is myasthenia gravis?   

Q23. What is the treatment of myasthenia gravis?

 

 

Q1. Abeer, a medical student, had a tooth ache. She went to the dentist and

the dentist advised her “filling” in a cavity in tooth. The dentist injected a local

anesthetic in the nerve pathway which carries the nerve impulses from the

area of tooth. Due to injection, Abeer did not feel any pain during the drilling

and filling procedure.

 

Information – local anesthetic block voltage gated Na+ channels.

Explain how this action of local anesthetic prevents the transmission of pain

impulses to the brain?

 

 

(Reference – See page 131 in ‘Human Physiology’ by Lauralee Sherwood)

CASE HISTORIES

Q2. A person was driving the car very fast and had a road accident.

He injured his Right Ulnar Nerve in the upper arm and had a spinal

cord injury also.

Later, Right Ulnar Nerve in the arm recovered but there was no

return of function caused by spinal cord injury.

 

Answer the following:

 

Why Ulnar Nerve (PNS) recovered?

Why Spinal Cord (CNS) did not improve?

As a Medical Student, with your knowledge of Physiology, what ways

can you suggest to improve his Spinal Cord regeneration?

 

 

(Reference – See Page 103 in ‘Human Physiology’ by Lauralee

Sherwood)