1. The answer is "<span>the energy required to start the reaction".
</span>This energy is called as activation energy of the reaction. If the activation
energy is high, reaction is slow. Enzymes help to carry out the reaction by
a new path by reducing the activation energy. But the energy of reactants
and the products remain as same as without enzyme.
2. The answer is "reaction in cells would be too slow to sustain life<span>".
</span>If the activation energy is very high for the reaction, then that reaction will
be very slow and will require more time<span> to complete the reaction. Then survival is
very low. Hence, the roll of enzymes is very important to sustain life.</span>
The bird population might have to migrate in search for food or may decline in numbers.
Explanation:
This is a concept of primary producers that is trees and secondary consumers that is mouse and bids. Due to the decline in raw material available the mouse population declines and this also affects the secondary consumers that are birds of prey like hawks, owls etc.