Photo AI
2. Clostridium tetani is a bacterium that can be found in soil - Edexcel - GCSE Biology Combined Science - Question 2 - 2019 - Paper 1
Question 2
2. Clostridium tetani is a bacterium that can be found in soil. It causes the infection tetanus. Children are vaccinated against tetanus. Explain why these children... show full transcript
Worked Solution & Example Answer:2. Clostridium tetani is a bacterium that can be found in soil - Edexcel - GCSE Biology Combined Science - Question 2 - 2019 - Paper 1
Step 1
Explain why these children do not get tetanus if the bacteria enter their body through a cut in the skin.
Answer
Children who are vaccinated against tetanus receive a vaccine that contains inactivated toxins produced by the bacteria Clostridium tetani. This vaccination leads to the development of immunity, which is crucial when the bacteria enter the body through cuts. The immune system can quickly recognize and respond to the toxin, preventing the illness. Additionally, the vaccine stimulates the production of memory cells that ensure a rapid immune response upon potential exposure to the actual bacteria, thereby preventing the onset of tetanus.
Step 2
Explain how these bacteria have become resistant to Colistin.
Answer
Bacteria can develop resistance to Colistin through several mechanisms. One common method is the acquisition of mutations that alter the structure of the bacterial cell membrane, making it less permeable to the antibiotic. Additionally, horizontal gene transfer can occur, where resistant genes are shared among bacteria. Overuse of Colistin, or not completing antibiotic treatments, contributes to selective pressure. This evolution allows resistant bacteria to survive and proliferate, leading to a population of organisms that can withstand the effects of Colistin.