GMS 6474 Exam Questions and Answers 100% Correct

GMS 6474 Exam Questions and Answers 100% Correct Lecture 2 Muscles can either be ____ or ____? - Answer- 1. Voluntary 2. Involuntary What is one question to ask when comparing voluntary to involuntary muscles? - Answer- How is the underlying tissue metabolized? Cardiac functional syncytial vs smooth muscle functional syncytial? - Answer- Cardiac - pacemaker cells cause contractions Smooth - vasodilation/vasoconstriction True/False: Smooth muscle has striations? - Answer- FALSE! what two factors determine the force production at the sarcomere level? - Answer- If they are arranged in parallel or series! True/False: skeletal muscle cells contain many nuclei and very long - Answer- TRUE! Myofibrils are responsible for what 3 things? - Answer- 1. tension generation 2. force production 3. shortening of muscle What is a sarcomere? - Answer- Basic unit of muscle that extends from Z-disc to Z-disc Sliding filament theory? - Answer- The thick/thin filaments do not change but the overlap does! H zone? - Answer- H for "heal" aka "light" only tails of myosin molecules *** THIS COULD DISAPPEAR DUE BC OF CONTRACTIONS** A-band? - Answer- both thick and thin I band? - Answer- only thin - extends both sides of the z-disc ***THIS WILL SHORTEN IF THE MUSCLE CONTRACTS*** What is a triad? - Answer- SR, T Tubule, SR Why is T-Tubule important? - Answer- muscle cells are really long so there needs to be something that connects the outside with the inside **allows for better communication system** ** action potentials would not reach the myofibrils if it werent for the T-tubules*** True/False: SR keeps Ca levels low? - Answer- TRUE! Lecture 3 - Answer- What are the 3 parts of the thick filament? - Answer- 1. tail 2. hinge aka neck 3. head Which part is responsible for the ATP activity? Aka the binding and splitting of ATP? - Answer- Head Specifically? - Answer- Myosin heavy chains The myosin light chains are responsible for what? - Answer- Modulating the ATP activity in cardiac/skeletal muscle When inidividual myosin molecules are placed in a ionic and salt solution, what happens? - Answer- The myosin heads will join together and tails will dimerize to form one thick cross bridge filament another reminder....what part of the myosin is responsible for the ATP activity? - Answer- The myosin heavy chains on the myosin heads what protein is responsible for in participating in the bipolar arrangement and packing into sarcomere? - Answer- Myomicin C protein Which protein holds the myosin heads together, instead of leaving them in space? - Answer- titin (attaches myosin to z disc) thin filament is what? - Answer- actin heavy chains of myosin are going to act upon what? - Answer- THE ACTIN! G actin vs F actin? - Answer- Glomerular vs filamentous What protein strand hides the active site on the actin? - Answer- Tropomyosin Which part of troponin is acted upon Ca? - Answer- C which two proteins anchor the thin filament to the Z-disc? - Answer- 1. alpha-actinin 2. capZ Z disc is made up of which two proteins - Answer- alpha actinin and CapZ Which component attaches the sarcolemma to the outside filaments/collagen? - Answer- Dystrophin Associated Complex _________ links the DAC with the extracellular matrix? - Answer- Laminin-2 (attaches to alpha/beta dystroglycans) a,b,g,d sarcoglycans are inside of the sarcolemma and are held together by what? - Answer- sarcospan Dystrophin anchors actin on what terminus? - Answer- N' C' terminus anchors what? - Answer- nNOS to border of sarcolemma Desmin is imp for what? - Answer- connects outside to inside Lecture 4 - Answer- Motor neurons that innervate the same muscle fiber will have the same ___ and ____? - Answer- metabolic, contractile phenotypes True/False: The muscle side of the neuromuscular junction is highly folded - Answer- TRUE! Ach diffuses across synaptic cleft and binds to ______ receptors? - Answer- nicotinic what happens when Ach binds to these ligand-gated receptors? - Answer- Na+ and K+ permeability increases! ---- End plate potential occurs true/false: the end-plate potential is stationary so it will only stay w/i the NM junction? - Answer- TRUE!