other proteins can be used to establish degrees of evolutionary relatedness between organisms. would you expect to find roughly the same number of differences in the amino acid chains when comparing organisms? explain your answer.

The lengthier that organisms have been detached the greater amount of random mutation would have arisen, and thus the larger the amount of different amino acids in the same proteins.

These changes are probable to be in regions that don't involve the active site, otherwise the protein would not function giving a obsolete organism. Similarly genes that encrypt proteins that are very vital to cellular function will be very similar in many animals despite having a common ancestor hundreds of years ago. This is because a small mutation in a very important gene is likely to stop its function and thus kill the cell. However proteins that are not so indispensable or present in many copies may be very different in different animals

hope it helps

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms