Calcium ions presents Ca+ binds to troponin which makes tropomyosin move out of way for myosin to attach. Cross-bridge attaches. ATP breakdown provides energy to ready the myosin head for a power stroke. Myosin head attaches to exposed binding site on actin and the power stroke is accomplished. Cross-bridge (Myosin head) springs from raised position and pulls on the actin filament. Cross bridges break, ATP binds to Cross-bridge (but is not yet broken down) Myosin heads are released from actin. As long as calcium ions and ATP are present, this walking continues until the musle fiber is fully contracted. Hope this helps!
There are two major sources of energy that power the earth's environmental systems, these are SUN AND THE EARTH'S INTERIOR HEAT.
The heat energy from the sun is the one responsible for processing all the external processes that occur in the atmosphere, hydrosphere and on the earth surface.
The energy from the earth's interior is the one that is respondsible for powering the internal processes that produce earthquakes, volcanoes eruptions and mountain formation.
<span>Penicillium does not seem to have sexual phase</span>
This answer would be a because
Germs are transferred from one bacteria to the next....
