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How Antibiotics Work Which of the following statements explain how the Gramicidi

ID: 858194 • Letter: H

Question

How Antibiotics Work Which of the following statements explain how the Gramicidin A antibiotic works? Select all that apply. The antibiotic disrupts the normal balance of ions in the bacterium, in which Na+ ions are excluded and K+ ions are retained inside. In a normal bacterial cell, K+ ions are excluded and Na+ ions are retained inside and the antibiotic disrupts this balance. Two molecules of Gramicidin A attach together in a coil that is positioned in the cell membrane like a tunnel. The inside of this coil is lined with non-polar groups that disrupt the contents of the cell by dispersion forces. A coil made from two molecules of Gramicidin A is anchored in the cell membrane creating a tunnel between the inside and outside of the bacterium. Ion-dipole forces from the polar groups lining the inner wall of this tunnel encourage the movement of ions. references

Explanation / Answer

When Gramicidin A attacks a bacteria, it forms a tunnel (hole) through the bi-layer membrane of the bacterium. Water molecules and sodium ions pass through this tunnel from inside the bacterium to outside. As a result, the balance of ions is disrupted and the bacterium is killed.

So the correct statments are second, and fourth statments describe how the antibiotic works.