Part I – The Tour
You are an intern working in the Atlanta, GA office of Dr.Priya Wayne, MD. Dr. Wayne is a specialist in rare neuromuscularand musculoskeletal disorders. You’ve been working with Dr. Waynefor the last year and due to this experience you’ve gained a greatdeal of knowledge about the human body and muscle physiology.You’re also a college student and working with Dr. Wayne hasallowed you to gain first-hand experience with some of the materialthat you’re learning in your human physiology course. Just lastweek you had to turn in an assignment comparing and contrastingdisorders of the neuromuscular junction. You learned all aboutseveral issues, including myasthenia gravis, sarin, curare,botulism, and Eaton-Lambert syndrome.
Today a group of high school students is coming for a tour andDr. Wayne has asked you to prepare some information about musclesto present to the students. Specifically, Dr. Wayne has asked youto discuss the neuromuscular junction (NMJ), skeletal musclecontraction, and explain some of the issues that can occur whensignaling between neurons and muscles does not go as planned.
Questions
Use the word bank to match the appropriate letter to thedefinitions/descriptions on the next page.
(a) Sodium
(b) Nicotinic acetylcholine receptor (nACh) (c) Myosin
(d) Actin
(e) Acetylcholine (ACh)
(f) Depolarization
(g) Motor end plate
(h) Acetylcholinesterase (AChE)
(i) Synaptic vesicles
(j) T-tubule
(k) Sarcoplasmic reticulum (l) Dihydropyridine receptor (m)Ryanodine receptor
(n) Synaptic terminal
(o) Sarcolemma
(p) Sarcomere
*These four undergraduate students contributed equally to thecreation of this case study and are listed in alphabeticalorder.
Case copyright held by the National Center for Case StudyTeaching in Science, University at Buffalo, State University of NewYork. Originally published September 29, 2016. Please see our usageguidelines, which outline our policy concerning permissiblereproduction of this work. Photograph by Victoria Garcia, OpenStax,
[email protected]:mU03zyTM@2/Interactions-of-Skeletal-Muscl>,cc by 4.0.NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE 1. ___ Thincontractile protein involved in cross-bridge formation, comes infilamentous or globular forms.
2. ___ Store neurotransmitters, and following a Ca2+ drivensignal, dump neurotransmitters into the synapse.
3. ___ The structure at the end of the axon that containsneurotransmitters and vesicles.
4. ___ The functional unit of the muscle fiber that includesthe A-band, I-band, H-zone and the M-line.
5. ___ The ion responsible for depolarizing the musclemembrane by traveling through the nACh receptor, down itselectrochemical gradient.
6. ___ Located on the sarcoplasmic reticulum and once opened,allows Ca2+ flow from the sarcoplasmic reticulum into thesarcoplasm.
7. ___ Thick filamentous contractile protein involved incross-bridge formation, has a club-like appearance with a“head.â€
8. ___ A neurotransmitter derived from choline; responsiblefor sending the excitatory signal in the neuromuscularjunction.
9. ___ These invaginations allow depolarization of the musclemembrane to quickly penetrate from the sarcolemma to themyofibril.
10. ___ Large and complex terminal formation by which an axonof a motor neuron establishes synaptic contact with a skeletalmuscle fiber, transmitting neural impulses to a muscle.
11. ___ The plasma membrane of a muscle fiber.
12. ___ The enzyme responsible for stopping the ACh signal.Functions by metabolizing ACh into choline, which is recycled, andacetate.
13. ___ Responsible for opening a ligand-gated Na+/K+ channelin the muscle membrane when the proper ligand binds to it.
14. ___ A L-type calcium channel in the muscle cell membrane,activated upon depolarization, couple depolarization signal torelease of calcium.
15. ___ An electrical change which brings the relative chargeof the inside of the cell more positive; necessary for transmissionof electrical impulses within a cell, or from one cell toanother.
16. ___ Modified endoplasmic reticulum, stores and releasescalcium.
Explain the organization/classifications of the Human NervousSystem.
1. Which component(s) will be your main focus in this casestudy
