OCR Biology Investigatory Project PDF

# Biology Investigatory Project ## **Effects of Antibiotics on Micro-Organism** ### Index - Introduction - Why are antibiotics used? - What are antibiotics? - Golden Timeline - Experiment ## **Introduction** Antibiotics are medicines that fight bacterial infections in people and animals. They...

# Biology Investigatory Project ## **Effects of Antibiotics on Micro-Organism** ### Index - Introduction - Why are antibiotics used? - What are antibiotics? - Golden Timeline - Experiment ## **Introduction** Antibiotics are medicines that fight bacterial infections in people and animals. They work by killing the bacteria or by making it hard for the bacteria to grow and multiply. Antibiotics work by killing bacteria or stopping them from multiplying. For example, antibiotics can kill bacteria by destroying crucial parts they need to survive, like their cell walls or DNA. Antibiotics can stop the growth of bacteria by preventing them from making certain proteins they need to multiply. ## Why are Antibiotics Used? Antibiotics may be used to treat bacterial infections. For example: - Bacterial infections which may be communicable or need antibiotics to cure. - If it carries a risk which has more complications and prevents some types of bacterial infections. ## **What are Antibiotics?** - Antibiotics are substances that work against bacteria. - It is like an agent which fights against bacteria to prevent disease. - It may kill the bacteria or inhibit the growth of bacteria. - They are not affective against viruses. - They can be given in different ways; tablets, capsules, liquids, creams, lotions or injection. - Examples of antibiotics include: flucloxacillin, penicillin, Amoxicillin, etc. ## **Golden Timeline** The timeline shows the history of antibiotic discovery and development. It also highlights important events, such as the discovery of penicillin, the emergence of antibiotic resistance, and the development of new antibiotic classes. | Year | Event | |---|---| | 1900 | First synthetic antibiotic used clinically | | 1928 | Penicillin discovered | | 1940 | Penicillin approved for clinical use | | 1950 | Streptomycin discovered | | 1960 | MRSA first detected | | 1970 | Last class of clinically-used NP antibiotic discovered | | 1980 | VRE first detected | | 1990 | VRSA first detected | | 2000 | First actinomycete genome sequenced | | 2010 | Plasmid-borne colistin resistance in Enterobacteriaceae. | The timeline is divided into different sections: - **Fungal natural products:** This section shows the natural products that inspired the development of many antibiotics. - **Synthetic antibiotics:** This section shows the different classes of synthetic antibiotics that have been developed since the 1930s. - **Golden Age:** This period, from the 1940s to the 1960s, saw the discovery and widespread use of many important antibiotics, such as penicillin and streptomycin. - **Antibiotic resistance:** This section highlights the increasing problem of antibiotic resistance. The timeline shows that antibiotic development has been a continuous process, with new classes of antibiotics being discovered and developed over time. However, the problem of antibiotic resistance is a growing concern. ## **Experiment** When a culture medium is developed using potato dextrose agar, we can observe that penicillin and terramycin have no colonies formed. Chloromycetin has 1-2 colonies formed and Streptomycin has 2-3 colonies formed. Of course, the control had formed 30-40 colonies. ## **Different Classes of Antibiotics** Different classes of antibiotics, their mechanisms of action, bacterial susceptibilities, and potential adverse events. - Bacteria have developed antibiotic resistance. These bacteria may infect humans and animals, for which treatment is harder. - Hence, antibiotic resistance leads to increased mortality. - This creates a need for us to change the way of understanding and treating. ## **Bibliography** - https://www.scribd.com/document/455940189/STUDY-OF-EFFECTS-OF-ANTIBIOTICS-ON-MICRO-ORGANISMS - https://www.nhs.uk/conditions/antibiotics/side - https://www.drugs.com/article/antibiotics.html - Google - Lab manual - https://www.nhsinform.scot