distance from 2 disc to 2 disc A bands containing myosin move closer together

Distance from 2 disc to 2 disc a bands containing

This preview shows page 7 - 12 out of 19 pages.

distance from 2 disc to 2 disc A bands containing myosin move closer together but do NOT shorten I bands shorten b c they define distance between A bounds of successive sarcomeres H bands containing myosin shorten
Image of page 7
5. Describe the basic structure of the thick (myosin) and thin (actin) filaments include actin, actin active sites, troponin, tropomyosin, myosine tail, myosin head (what is the function of each of these components). Thin filaments actin polymer formed of 300 400 globular subunits CG actin arranged in a double row and twisted to form a helix Tropomyosin A different type of protein lies within the groove between the double row of G actin monomers Troponin Attached to the tropomyosin rather than directly to the actin is a third type of protein troponin Troponin is a complex of 3 proteins Actin active sites Myosin binding site on the globular actin protein Thick filaments myosin consists of myosin tail and myosin head which forms the cross bridges that extend out from the myosin toward the actin
Image of page 8
6. Describe the components of the Neuromuscular junction (NMJ), what is the function of these components (synaptic terminal, acetylcholine, synaptic cleft, motor end plant, acetylcholineesterase). d 1 Myosin tail myosin subunit that connects the myosin head Myosin head two globular heads that serve as cross bridges Contains Actin binding site and ATP binding site Actin binding site binds to actin on both sides and pull actin toward the center Also function as myosin ATPase enzymes splitting ATP into ADP and pi Synaptic terminal specialized to release NT of the presynaptic cell The terminals release transmitter substances into a gap called the synaptic cleft between the terminals and the dendrites of the next neuron Acetylcholine NT a chemical released by a nerve cell or neuron Causes muscles to contract activates
Image of page 9
7. Describe the process of sarcomere contraction starting from the nerve impulse at the neuromuscular junction and ending with contraction. Make sure to include neurotransmitters, how Ca++ is released into the cell, what Ca++ does, and the roles of actin, myosin, troponin, tropomyosin, and ATP. U l l l pain responses 4 regulates endocrine 4 REM sleep functions synaptic cleft space between neurons at a nerve synapse across which a nerve impulse is transmitted by a NT Motor end plates Neuromuscular junction's are specialized chemical synapse formed at the sites where the terminal branches of the axon of a motor neuron contact a target muscle cell causes electrical activation of skeletal muscle fibers Acetylcholinesterase Enzyme that catalyzes the breakdown of acetylcholine and some other choline esters that function as neurotransmitters
Image of page 10
Somatic Motor Neuron ACh released Ach NT Sarcolemma NT binds to nicotinic A Ch receptors opens ligand Cchemically gated channels Nat diffuses in producing depolarizing stimulus AP Pr oduced T Tubules AP travels down the Saco lemma to the T tubules AP opens v G Catt channels channels in T tubule are mechanically coupled to cast release channels in SR
Image of page 11
Image of page 12

You've reached the end of your free preview.

Want to read all 19 pages?

  • Spring '17
  • Tony Sanchez
  • Muscle fascicle

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

Stuck? We have tutors online 24/7 who can help you get unstuck.
A+ icon
Ask Expert Tutors You can ask You can ask You can ask (will expire )
Answers in as fast as 15 minutes