a subset of a population of birds leaves its habitat on the mainland and colonizes a nearby island. the birds, after a period of time, become reproductively isolated. the island sinks and the population of birds that lived on the island returns to itsoriginal habitat. which of the following statements about these bird populations is true?

the answer is: the „power stroke“ step.

muscle contraction can be divided into a few steps:

1. the release of ach (acetylcholine) in the synaptic cleft, binding of ach for its receptor and consequently opening of the ca channels.

2. the release of ca, binding of ca for the troponin

3. troponin shifting the tropomyosin, which was blocking the active site on the actin

4. myosin heads attaching to actin by breaking down atp to adp+ pi

5.   formation of the ‘cross-bridge’ on the active site of the actin filament by myosin head

6. “power stroke” -the cross bridge pulls actin, which slides over the myosin

9.     7. the release of adp completes the cross-bridge movement and atp attaches to myosin, breaking the actin-myosin cross bridge.

barometer is an instrument used to measure the atmosphere's pressure. the high air pressure relative to average levels is associated with calm and sunny weather. on the other hand, low pressure is associated with bad weather, high winds, and rain.