Plants and animal cells are examples of À cells as they contain both nuclei and organelles.
Question 26 2 points)
The Great Rift Valley in Africa and the Mid-Ocean Ridge were all created by a
A boundary where two tectonic plates
pull apart.
Question 27 (2 points)
Match the type of rock with the correct definition

c is the answer to this question. altitude affects the weather because air molecules evaporate.

i think its both a and b

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.