Which of these binds to receptor molecules on the host cell membrane?

Glycoproteins is the one that binds to the receptors molecules on the host of the cell membrane. Glycoproteins on the viral envelope recognize and bind to receptors on the host cell. The answer in this question is the glycoproteins on the viral envelope bind to receptors on the host cell membrane.

The answer is joseph is observing the colour of the reaction mixture to see whether proteins are present in the given solution.

I'm soooo sorry but i can't answer but you can ask another professor