The Chemicals of Life (Biology)?

Question

Just 2 questions that I have been trying to figure out for about 3 hourse now!!!

1. The mean Mr (relative molecular mass) of an amino acid is 110. The Mr of a particular protein is 40 000. Calculate the number of amino acids that make up this protein! Please can you show me how to answer this question!!!

2. How is it possible for different proteins to have the same relative molecular mass?

Answer 1

1. Since an amino acid weighs 110 Mr, and your protein weighs 40,000 Mr, all you have to do is divide the weight of the protein with the weight of each amino acid:

40 000/110 = 363.6 amino acids or roughly 364 amino acids.

2. This is possible because they would have the same NUMBER of amino acids that comprise their structures. The weight depends on the number of amino acids in the protein, not on the kinds present in it since all amino acids would have roughly the same weight.