a student observes that the grass in his yard begins to die during the hot summer which of the folowing is a valid hypothesis for why the grasses seems to be dying

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.

z is the answer.

(sorry caplock) lol

                                                happy valentines

hybridization actually occurs frequently in nature. evolution is derived from the process of hybridization that creates things with different traits. this leads to the species changing and evolution occurring. hope this : )