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.
Hello Daniel......
Have a beautiful and joyful day ahead.
<span> Because when bacteria convert ammonia into nitrates and nitrites, producers need them to make proteins, and then consumers eat the producers and reuse the nitrogen to make their own proteins.
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Answer:
A
Explanation:
A) The extent to which their overall activities afdect cycad flowers.
The following is a safety consideration when hunting wild turkey is Use a rooster call, avoid using a hen call.
<h3>Will Turkey Hunting What should you do if you see another hunter nearby?</h3>
If you do see another hunter, don't move. Stay perfectly still, and either speak to the hunter in a normal voice or call out loudly if the hunter is farther out.
Make absolutely sure that the hunter knows you're there before you move. If you use camouflage, cover your entire body, contain your face.
Thus, option "A" is correct, Use a rooster call, avoid using a hen call.
To learn more about wild turkey click here:
brainly.com/question/6884019
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