Answer:
The correct answer is 3: "<em>High levels of Ca2+ are expected to be found </em><em>within the sarcoplasmic reticulum</em>".
Explanation:
Muscular contraction is a highly regulated process that depends on free calcium concentration in the cytoplasm. Amounts of cytoplasmic calcium are regulated by <u>sarcoplasmic reticulum</u> that functions as a storage of the ion.
When a nerve impulse reaches the membrane of a muscle fiber, through acetylcholine release, the membrane depolarizes producing the entrance of calcium from <u>extracellular space</u>. The impulse is transmitted along the membrane to the sarcoplasmic reticulum, from where calcium is released. At this point, <em>tropomyosin is obstructing binding sites for myosin on the thin filament</em>. The calcium channel in the sarcoplasmic reticulum controls the ion release, that activates and regulates muscle contraction, by increasing its cytoplasmic levels. When <em>calcium binds to the troponin C</em>, <em>the troponin T alters the tropomyosin by moving it and then unblocks the binding sites,</em> making possible the formation of <em>cross-bridges between actin and myosin filaments.</em> When myosin binds to the uncovered actin-binding sites, ATP is transformed into ADP and inorganic phosphate.
Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.
Answer:
Boiling point.
Explanation:
This is because when water boils, it is changing from a liquid to a gas. This is a state change/physical change.
I hope I helped!
In order to determine this, we will require some pieces of meat, preferably taken from the same animal and from the same area and of similar size. After the pieces of meat are obtained, they are sealed in a container with equal quantities of meat tenderizer. Then, keep the containers in different temperatures.
After fixed time intervals, say 3 hours, record the appearance and texture of the meat. Repeat this until readings for 5-6 time intervals have been obtained.
<span>Being male, the levels of the hormone Testosterone
is higher in Paulo’s body than in his sister, Liette’s body. As a result of the
higher testosterone levels in Paulo’s body, it’s reasonable to expect him to
experience greater physical aggression than his sister.</span>
The monomers<span> of these organic groups are:</span>Carbohydrates...<span>monosaccharides. Lipids...glycogen and fatty acids...Nucleic acids...nucleotides.
I think.....
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