A scientist wishes to test a new antibiotics ability to treat bacterial infections. she tests her hypothesis that the antibiotic will effectively treat a stubborn bacterial infection by infecting rats with a stubborn infectious bacteria and treating them with the new antibiotic, she then determines how many of the rats recover from the infection. what is missing from her experimental design?

Antibiotics are medicines used to kill bacteria. Over time, certain groups of these germs may adapt to these medicines. They may change in such a way that antibiotics can′t kill them. The term for this is antibiotic resistance.

Bacteria are very small organisms. They can enter your body. Some of them are harmless and may be helpful. But some of these germs can be harmful. When these multiply inside your body, they can cause disease.

Before antibiotics, people often got very sick from bacterial infections. With these medicines, it is now easy to treat many of these infections.

Antibiotic resistance is a serious concern throughout the world. It can lead to illnesses that are very hard to treat. Standard antibiotics for treating a disease may no longer work in these cases. Other medicines may also not help. As a result, resistance to antibiotics is becoming more common.