In terms of differences, eukaryotic cells are much larger and more complex than prokaryotic cells. On average, a typical eukaryotic cell is about 1,000 X larger in volume than a typical prokaryotic cell.
This means both drugs (amoxicillin and penicillin) can treat a wide variety of infections. However, unlike amoxicillin and penicillin, the routinely prescribed drug, metronidazole, has a more selective action towards anaerobic bacteria. These bacteria are the ones causing the signs and symptoms of bacterial vaginosis.
Penicillin antibiotics are used to treat treat urinary tract infections, upper respiratory tract infections, lower respiratory infections, skin infections, bacterial infections, gastrointestinal infections, meningitis, and pneumonia. They work by killing the bacteria that is causing the infection.