Midterm Lab Exam (15%) Contraction and Relaxation of Skeletal Muscle Fibers KG STUDENT PDF

Midterm Lab Exam (15%) Date: Wednesday Oct 2nd Time: Sitting 1: 5:30-6:30pm Sitting 2: 6:40-7:40 pm Exam time and room Assignments are posted to Moodle Exam Room: MSB 225 AND MSB 147 Exam Length: 60minutes All of the content from labs 0-3 will be test...

Midterm Lab Exam (15%) Date: Wednesday Oct 2nd Time: Sitting 1: 5:30-6:30pm Sitting 2: 6:40-7:40 pm Exam time and room Assignments are posted to Moodle Exam Room: MSB 225 AND MSB 147 Exam Length: 60minutes All of the content from labs 0-3 will be testable on the midterm Students registered to write with the TCAL will go directly to the library to write their exam Students will be permitted a Cheat Sheet for the lab exam. Rules are as follows: 4x6 inch cue cards (each student will get 2 in class) You may use both sides, but no additional flaps or pieces can be added Your name and student number must be on it No other aids allowed (ie magnifying glass or hand lens)  Example Questions: EXAMPLE EXAM SLIDE #1 I. What is the name of this tissue? II. What primary tissue type this? III. Identify feature “A” A  Skeletal Muscle Physiology and the Neuromuscular Junction Whole muscle surrounded by Fascicle Muscle Myofibril Fiber Epimysium surroundedsurrounded by by by surrounded Endomysium Perimysium and Sarcoplasmic Sarcolema Reticulum Thick and Thin Filaments Neuromuscular Junction  Action potential Acetylcholi arrives at terminal ne (Ach) end bulb. Calcium Voltage-gated Ions (Ca2+) Calcium channels Sodium open and Ca2+ Ions (Na+) rushes in. Synaptic vesicles migrate and fuse with membrane – releasing ACh into synaptic cleft. Motor End  Action potential Acetylcholi arrives at terminal ne (Ach) end bulb. Calcium Voltage-gated Ions (Ca2+) Calcium channels Sodium open and Ca2+ Ions (Na+) rushes in. Synaptic vesicles migrate and fuse with membrane – releasing ACh into synaptic cleft. Muscle Action Potential ACh binds This to ligand- generates gated Na+ an action channels potential, allowing which Na+ to travels into along the sarcoplas sarcolemm m. Motor End a. Excitation- Contraction Coupling  Voltage- Terminal Ca2+ release gated Ca2+ cisterns of channel channels SR Sarcolemm a T Ca2+ tubules ions Sarcoplasm  AThe muscle This action causes 2+ the voltage-gated The Ca potential CaCa surrounds2+ 2+ travels release channels the thick along channels detect and the tothe thin sarcolemma open, allowing change filaments oflarge the voltage in the muscle amounts offiber, and sarcoplasm, Ca 2+ and penetrates down the T tubules. to flow undergo binding a out with of the SR andinto conformational troponin, the sarcoplasm. change. initiating a muscle contraction AP Calcium Ions (Ca2+) Tropomyos Tropon in in Acti Myosin-binding site n (covered by AD tropomyosin P Calcium binds to the troponin. The Myosin-binding sites are troponin-tropomyosin NOW exposed complex changes allowing myosinthe shape, shifting heads to attach out tropomyosin forming of cross-bridges. the way and exposing the myosin Calcium Ions (Ca2+) Tropomyos Tropon in in Acti AD n P Myosin cross-bridges rotate toward the Myosin-binding center sites are of the sarcomere NOW (the exposed Power Stroke) allowing the releasing myosin ADPheads to attach molecule. This forming slides the cross-bridges. thin filament past the thick filament Contraction Cycle  As Myosin Myosin myosin heads heads heads arebind hydrolyze bound ATPto(into to ADP ATP, myosin and an the binding cross-bridges inorganic sites onmolecule) phosphate an detach actin and they molecule from the become via actin cross- reoriented and molecule. bridges. energized. Myosin head ATP ADP P Myosin Protein  Myosin Myosin heads heads bind hydrolyze again ATP to the (into myosin ADP binding and an inorganic sites on the phosphate actin molecule, molecule) reforming and they become the cross-bridges, reoriented releasing and the energized. phosphate molecule in the process. ADP P AD P P Myosin Protein  Myosin cross-bridges As Myosin myosin heads heads rotate arebind bound toward to to the center of the sarcomere ATP, myosin the(the binding cross-bridges Power sites Stroke) on an releasing the ADP molecule. detach actin molecule from This the slides via actin cross- the thin filament past the thick molecule. bridges. filament towards the M line AD P P Myosin Protein Detachment of myosin ATP hydrolysis: The myosin from actin: As ATP binds head hydrolyzes ATP (into to the ATP-binding site on ADP and a molecule of the myosin head, it phosphate). This reaction detaches from actin. reorients and energizes the myosin head. Attachment: The energized myosin ATP head attaches again Power Stroke: to the myosin-binding AD Myosin cross- site on actin via cross- P ADP bridges rotate bridges and releases toward the center of the phosphate the sarcomere P molecule in the releasing the ADP process. molecule. This slides the thin filament past the thick filament towards the M line  AT AT P P Calcium active transport pumps Sarcoplasm Calcium Ions (Ca2+) Tropomyos in Tropon in Acti Myosin-binding site n (covered by tropomyosin Calcium is released, and the troponin- tropomyosin complex slides back into place blocking the myosin-binding sites on the actin molecule.  M line M line Muscle GIF (also linked on moodle) : http://tabletopwhale.com/ This images is not included in student ppt (Muscle EM) 2014/08/12/a-users-guide-to- muscles.html  Neuromuscular Junction These images are testable and are included in student ppt Neuromuscular Junction These images are testable and are included in student ppt This images is not included in student ppt (teased muscle slide  Iworx: TENS Intensity Time off of shock between pulses Amp #P W(ms) T off(s) #T IT (ms) HP 5.0 1 5 1 1 0.05 0 Number of pulses - Use Autoscale almost CONSTANTLY - Use mountain buttons to change how much time is on screen Less time - Threshold value shown on X axis of the More time screen screen shown on the X - READ THE MANUAL (ie the graphed axis data moves