Answer and Explanation:
In rest, attraction strengths between myosin and actin filaments are inhibited by the tropomyosin. When the muscle fiber membrane depolarizes, the action potential caused by this depolarization enters the t-tubules depolarizing the inner portion of the muscle fiber. This activates calcium channels in the T tubules membrane and releases calcium into the sarcolemma. At this point, tropomyosin is obstructing binding sites for myosin on the thin filament. When calcium binds to the troponin C, the troponin T alters the tropomyosin by moving it and then unblocks the binding sites. Myosin heads bind to the uncovered actin-binding sites forming cross-bridges, and while doing it ATP is transformed into ADP and inorganic phosphate which is released. Myofilaments slide impulsed by chemical energy collected in myosin heads, producing a power stroke. The power stroke initiates when the myosin cross-bridge binds to actin. As they slide, ADP molecules are released. A new ATP links to myosin heads and breaks the bindings to the actin filament. Then ATP splits into ADP and phosphate, and the energy produced is accumulated in the myosin heads, which starts a new binding cycle to actin. Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.
The domain archaea are able to tolerate extreme environments.
Answer is D
There are 3 types Divergent is when two plates are moving apart,Convergent is when two plates are colliding and Transform boundaries is when plates slide pass each other.Therefore Convergent plates are depicted.
Answer:
The correct answer is arteries.
Explanation:
The ventricles refer to the lower two chambers of the heart. The prime function of the ventricles is to pump blood to the rest parts of the body. Arteries refer to the vessels, which will be the first one to come in contact with the blood from the ventricles.
Arteries are the blood vessels, which mediate blood away from the heart to the other parts of the body like tissues and lungs. The arteries are strong, thick, and exhibit elastic walls. The distinct types of arteries comprise elastic arteries, muscular arteries, and arterioles.
answer:
the planets revolve around the sun
