Summary
Microbiology involves the study of microorganisms, including bacteria and viruses, and their growth, structure, and life cycles.
- Uncontaminated Culture Preparation — involves growing microorganisms in a controlled environment using aseptic techniques. Example: Sterilizing equipment and using sterile transfer methods.
- Bacterial Growth Curves — show the growth phases of bacteria in a culture, including lag, log, stationary, and death phases. Example: Sigmoid growth curve.
- Structure of Bacteria — unicellular organisms with a cell membrane, cytoplasm, and circular DNA. Example: Bacteria may have flagella for movement.
- Structure of Virus — acellular particles with genetic material and a protein coat. Example: HIV has a protein coat with glycoprotein spikes.
- Viral Life Cycle — includes lytic and latent cycles, where viruses replicate within host cells. Example: Herpesviruses can enter latency.
Exam Tips
Key Definitions to Remember
- Aseptic technique
- Binary fission
- Lytic cycle
- Latent cycle
Common Confusions
- Difference between bacteria and viruses
- Understanding bacterial growth phases
Typical Exam Questions
- What is the purpose of aseptic technique? To prevent contamination of cultures by unwanted microorganisms.
- How do bacteria reproduce? Through binary fission, where one cell divides into two identical cells.
- What is the difference between the lytic and latent cycles? The lytic cycle results in host cell lysis, while the latent cycle involves dormant viral DNA in the host.
What Examiners Usually Test
- Understanding of bacterial growth curves
- Differences in structure between bacteria and viruses
- Steps in preparing uncontaminated cultures