Question

when a bacterial infection does not respond to being treated with antibiotics, phage therapy might be used. in phage therapy, a doctor will deliver a specific bacteriophage to a patient’s body. after phage therapy, some patients’ bacterial infections were eliminated. figure 1 shows two structures involved in phage therapy, represented by structure x and structure y. figure 1: structure x interacting with structure y diagram of structure x (bacteriophage) interacting with structure y (cell surface with receptor proteins) a change to which component in figure 1 would prevent structure x from binding to structure y? a. the receptor protein structure b. the peptidoglycan in the cell wall c. the abundance of structure x molecules d. the abundance of structure y molecules

Explanation:

To prevent Structure X (bacteriophage) from binding to Structure Y (bacterial cell), we need to disrupt the binding interaction. The binding occurs via the receptor protein on Structure Y's surface (bacterial cell membrane). Changing the receptor protein structure (Option A) would alter the binding site, preventing Structure X from attaching. Peptidoglycan (Option B) is part of the cell wall, not directly involved in phage - receptor binding. Changing the abundance of Structure X (Option C) or Y (Option D) molecules doesn't directly prevent binding; the key is the receptor structure that facilitates the interaction.

Answer:

A. The receptor protein structure