Question

Molecular weight of protein is:
A. > 12000
B. < 6000
C. < 12000
D. 600 – 3000

Answer 1

Hint: As protein made up of a hundred to a thousand of smaller structural units which is called amino acid. There are majorly 20 amino acids which are arranged in different manners to generate a protein. Molecular weight of proteins can be calculated by sum of individual weight of all amino acids which are used to build the protein.

Complete Step by Step Solution:
Amino acid, its name itself suggesting that amino acid is a combination of amino group and acid (carboxylic acid) such as

This type of amino acid combines with one or more other amino acids through peptide linkage. If there is less number of peptide linkage then it is called oligopeptides whereas if large number of Question:

For proteins which are polypeptides will consist 100 to 1000 of amino acids which together give average molecular weight greater than 1000 to 10,000 and can cross a million value. For sake of convenience, 110 Dalton or 110 amu is the average weight of single amino acid. After multiplying this value of weight to the total number of amino acids present in protein, give the average molecular weight of that protein.
So, molecular weight of protein must be greater than 12,000, thus, the correct option is A.

Note: It is important to note that we can calculate average molecular weight of protein because of the presence of many other variable groups along with carbon, nitrogen, carbonyl group, hydrogen and Sulphur and also due to the complexity of polypeptides.