(RM02}one student made the incomplete diagram shown below to represent the relationship between magma, igneous rocks, and metamorphic rocks Magma
Igneous
rocks
Metamorphic
rocks
Which of these is the correct next step to complete the diagram?
O Put an arrow labeled heat and pressure, pointing from magma to igneous rocks
O Put an arrow labeled heat and melt, pointing from metamorphic rocks to magma
O Put an arow labeled deposition and lithification, pointing from igneous rocks to magma
O Put an arrow labeled cools and crystallizes,. pointing from igneous rocks to metamorphic rocks

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.