What is the best definition of activation energy
a) the energy is required to end a chemical reaction
b) the energy is required to bind substrate to an active site
c)the energy required to form or break the bonds of reactant molecules
d)the energy required to re-form bonds in products molecules

What part of the brain is highlighted in the diagram below?

Why do we perceive objects as retaining their brightness under different lighting levels?

The graph shows the amount of global warming happening in different ecosystems. which populations of organisms will likely decline the most as a result of climate change, and why? a.coral reefs because of the loss of the symbiotic algae living within their bodies b.penguin populations because the fish they eat will move into warmer waters c.mountain-dwelling birds because rising sea levels will relocate their food sources d.large cats in the rainforest because of decreased habitat loss for their prey