A conjugated protein is a protein that functions in interaction with other (non-polypeptide) chemical groups attached by covalent bonding or weak interactions. Many proteins contain only amino acids and no other chemical groups, and they are called simple proteins.

Introduction:
Conjugated proteins, also known as compound proteins, are macromolecules composed of amino acids that are covalently bonded to other chemical groups. These chemical groups may include carbohydrates, lipids, nucleic acids, or metal ions. Conjugated proteins play vital roles in various biological processes such as enzymatic activity, cell signaling, and transport.

Explanation:
Among the given options, peptone is not a conjugated protein. Peptone is a mixture of peptides and amino acids obtained by the partial hydrolysis of proteins. Let's discuss the other options to understand why they are conjugated proteins.

Glycoprotein:
Glycoproteins are proteins that have covalently attached carbohydrate chains. These carbohydrates can be attached to the protein through either N-linked glycosylation or O-linked glycosylation. Glycoproteins are involved in various biological processes such as cell recognition, immune response, and cell adhesion.

Chromoprotein:
Chromoproteins are proteins that contain non-protein chromophores, which are responsible for their color. Examples of chromoproteins include hemoglobin (responsible for the red color of blood) and phytochrome (responsible for the red/far-red light sensing in plants).

Lipoprotein:
Lipoproteins are proteins that are combined with lipids. They play a crucial role in transporting lipids through the bloodstream. Lipoproteins are classified into various types based on their density, such as high-density lipoproteins (HDL) and low-density lipoproteins (LDL).

Conclusion:
In summary, among the given options, peptone is not a conjugated protein. Peptone is a mixture of peptides and amino acids obtained by the partial hydrolysis of proteins. On the other hand, glycoproteins, chromoproteins, and lipoproteins are all examples of conjugated proteins.

Peptones are linear chains of amino acids and do not contain other molecules. Phosphoproteins contain phosphorous, lipoproteins contain lipids and chromoprotein are flavoproteins which contain FMN and FAD, in addition to amino acids.