The lock-and-key mechanism refers to
the complementary shapes of an enzyme and a substrate.
the attractive forces between an enzyme and a substrate.
the ability of an enzyme to lower the activation energy of a reaction.
the ability of an enzyme to “unlock” the products of a reaction.

Ricardo notices that when he plays soccer in the rain, his ball does not seem to go as far after a kick. what is the best scientific question that ricardo could ask about this observation? is soccer better played in the rain or sun? how does rain affect the distance a soccer ball can travel? how does rain affect the speed of a soccer ball? is soccer affected by the rain?

In this experiment, the was intentionally manipulated. it is the independent variable. the dependent variables that were measured were the

Why does sexual reproduction result in more genetic variation in a species