Describe co-evolution and how the concept applies to
floweringplants and animals?

Process by which two organisms evolve structures and behaviors in response to change in each other over time.

If a plant species evolves a new defense against an herbivore, such an thorns or poisonous secretions, this induces a new pressure on that herbivore to select for different individuals, such as plants that remain tasty and readily edible.

In turn, these newly sought-after plants, if they are to survive, must overcome that new defense; in addition, the herbivores can evolve thanks to individuals that happen to have traits that make them resistant to such defenses

cuz some people don't have enough food. that's why we need more ppl to donate food to the hungry.

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.