All of the following are true regarding proteoglycans, EXCEPT:-

Chondroitin sulfate is a glycosaminoglycan -> option 1 is true Proteoglycan = core protein (Amino acid) + Glycosaminoglycan (sugar) -> option 3 is true Sulfate and acetyl groups confer negative charge to the amino acids -> option 4 is true As they are negatively charged, they can hold large amount of water, therefore -> option 2 is wrong.