Answer:
jneuschafer is such a chad he didnt even add the answer for the points. but yeah, what he said
Explanation:
In a cell, there are several parts of it that are there to stop this from happening. Cancerous cells do not have the genetic code to stop growing and reproducing. A regular cell will actually destroy itself it there is a mutation. If it does not get destroyed, it could potentially be tumorous, then it could eventually be cancerous.
Answer:
When a muscle cell contracts, the myosin heads each produce a single power stroke.
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, <em>tropomyosin is obstructing binding sites for myosin on the thin filament</em>. 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 liberated. Myofilaments slide impulsed by chemical energy collected in myosin heads, <u>producing a power stroke</u>. 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.
<span>Bivalvia - Clams, Oysters, Scallops and Mussels.
Cephalopod - Octopi, Squids, Cuttlefish, and the Chambered Nautilus.
Gastropoda - Snails and Slugs.
<span> Polyplacophora - Chitons.</span></span>
