Defence against disease - antibiotics Flashcards
What are antibiotics?
Drugs that inhibit the growth of microorganisms
Antibiotics predominantly target bacteria, not viruses.
How do antibiotics affect eukaryotic cells?
They do not harm the cells of the infected organism
This is due to antibiotics blocking specific processes in prokaryotic cells.
Which processes can antibiotics target in prokaryotic cells?
- Transcription
- Translation
- DNA replication
- Ribosome function
- Cell wall formation
Targeting these processes is what makes antibiotics effective against bacteria.
From which organisms are some antibiotics derived?
Living organisms such as saprotrophic fungi
An example is penicillin, produced by fungi in the genus Penicillium.
What is penicillin and how does it function in nature?
An antibiotic produced by certain fungi that helps them compete by killing nearby saprotrophic bacteria
Penicillin’s antimicrobial secretions are a natural defense mechanism.
Can antibiotics be synthesized in a laboratory?
Yes
This allows for the creation of antibiotics that may not occur naturally.
Why is penicillin not effective against all bacteria?
- Thicker cell walls which reduce permeability
- Enzymes which breakdown penicillin
These factors contribute to antibiotic resistance in certain bacteria.
Are antibiotics effective against viruses?
No, antibiotics are ineffective against viruses
Viruses are non-living particles without cell structure.
What distinguishes viruses from cells?
Viruses have no metabolism or cell structure
They rely on host cells for replication.
How do viruses replicate?
By using the host cell’s mechanisms for transcription, translation, and other metabolic pathways
This makes it impossible for antibiotics to target viral processes.
What are antivirals?
Drugs that target viral enzymes without harming the host cell
Antivirals are specifically designed to combat viral infections.
