Answer;
Pre-treatment with the carbohydrate component alone prevents bacteria attachment to the animal cells.
Step-by-step explanation;
Glycoproteins occur on cell surfaces and many are actively secreted from cells and are thus relatively accessible to biochemical investigations. Some glycoproteins are amongst the best characterised of proteins, and biochemistry students will undoubtedly have heard of some glycoproteins even if they fail to appreciate that they are glycoproteins.
-Bacteria are able to bind to cells by recognising sugars on the cell surface. For instance E coli and Salmonella typhimurium both adhere to epithelial cells and scavenging leukocytes via Man residues on the surfaces of the target cells, Viruses can also bind to target cells using glycoproteins.