Answer:
<u>Once the myosin-binding sites are exposed, and if sufficient ATP is present, myosin binds to actin to begin cross-bridge cycling. Then the sarcomere shortens and the muscle contracts. In the absence of calcium, this binding does not occur, so the presence of free calcium is an important regulator of muscle contraction.</u>
<h3><u>
</u></h3>
The jugular veins are the veins responsible for bringing deoxygenated blood from the head to the heart. There are two sets of jugular veins, the internal and external ones. In pigs, the internal and external jugular veins are similar in size, while in humans the internal jugular vein is bigger in diameter than the external.
enzyme A becomes less effective earlier than enzyme B
and enzyme b stays effective at higher temperatures than enzyme a
1- male skull
4- female skull
also sorry i couldn’t answer more im not studying that at the moment