Muscle contraction

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Muscle contraction
Review the videos below on the steps of muscle contraction:
1) Events at the neuromuscular junction
These videos illustrate the steps that occur for skeletal muscle cells, which are very similar to cardiac, heart, muscle cells which contract in a very similar way.
1. Now outline how alterations at the chemical level cause complications at the organismal level: How does crude oil interrupt heart cell signaling and overall heart cell function? What does this do to the fish?
Crude oil interrupted the ability of the heart to beat regularly and effectively. Crude oil is a mixture of chemicals that are toxic to all living mammals. Crude oil contained toxic compounds like "polycyclic aromatic hydrocarbon" (PAHs) that is found in coal tar, creosote, air pollution and stormwater runoff from the land. PAH can persist for many years in the aftermath of an oilspill. Crude oil interferes with cardiac cell excitability, contraction and relaxation that are vital processes for normal beat to beat contraction and pacing of the heart. Crude oil also disrupt the specialized ion channel pores in which molecules can flow in and out of the cells. The passage of small molecules in and out of cells can control the heart rate and contraction in the cardiac muscle cell.
Researcher had also found that oil can blocks the potassium channels distributed in heart cell membranes, increasing the time to restart the heart on every beat. The movement of ions into and out of the cells will affect how the heart beat. Crude oil interfere with the vital signaling process known as "excitation contraction coupling" that are essential for the hearts cells to function properly.

2. An outline of the research techniques used in this study, including brief description of each technique.
X-ray diffraction techniques, protein purification, coimmunoprecipitation are used in this study.
X-ray diffraction - a technique that is used to determine the crystalline structure of the myosin and actin region. The crystallographic structure have shown the molecular mechanism by which ATP binding leads to actin dissociation and force generation.
Coimmunoprecipiaton is a technique used to determine whether actin interacts with myosins.
Protein purifications- these actin and myosin proteins need to be purify by this method.

1) Events at the neuromuscular junction:

The sequence of events in the neuromuscular junction are highlighted below:
1) The first event is that the action potential arrives at the axon terminal. When the exon potentials arrives at the axon terminal, a voltage regulated calcium channels will open up allowing calcium ions to enter the axon terminal. When the action potential moves down the axon, there is a reversal of ...