Using what you know about the structures of the amino acid side chains and the mechanisms presented in this chapter, which of the following amino acid side chain may play the following roles in an enzymatic mechanism: a. participate in proton transfer, b. act as a nucleophile

a. participate in proton transfer - His

b. acts as a nucleophile - Ser

Explanation:

Enzymes are regulated because they are proteins. They are categorize based on how they catalyze. Heat weakens and inactivates the enzymes because of non covalent interaction. His amino acid participate in proton transfer because it is able to act as an acid as well as a base while Ser amino acid can act as nucleophile.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

i do not get it   at all