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What type of pathogens are antibiotics used for?

Antibiotics are used to treat bacterial infections. They are not effective against viruses, fungi, or other types of pathogens.

Why do antibiotics not effect Human cells?

Antibiotics do not affect human cells because they target specific features of bacterial cells. For example, antibiotics may target bacterial cell walls, protein synthesis machinery, or DNA replication processes, which are different from those in human cells.

describe the three ways in which Antibiotics can work

Beta Lactam: inhibiting the synthesis of bacterial cell walls, leading to cell lysis and death.

Macrolides: inhibit bacterial protein synthesis by binding to the bacterial ribosome, preventing the production of essential proteins.

Quinolones: These antibiotics interfere with bacterial DNA replication by inhibiting enzymes like DNA gyrase and topoisomerase, which are crucial for DNA synthesis.

describe how antibiotics may be harmful.

Antibiotics can be harmful by disrupting the balance of the gut microbiome, leading to reduced bacterial diversity and dysbiosis. This can result in increased susceptibility to infections, compromised immune function

how our first antibiotic – penicillin, was discovered and by whom.

Penicillin, the first true antibiotic, was discovered by Alexander Fleming in 1928 at St. Mary's Hospital in London. Fleming observed that a mold called Penicillium notatum produced a substance that killed a wide range of harmful bacteria. This discovery led to the development of penicillin as a treatment for bacterial infections

Describe the difference between gram positive and gram negative antibiotics.

Gram-positive antibiotics are effective against bacteria that have a thick peptidoglycan layer in their cell wall

Gram-negative antibiotics target bacteria with a thinner peptidoglycan layer but have an outer membrane that can be more resistant to certain antibiotics.

Why is there a need to test the bacteria that is causing the infection?

to determine the most effective antibiotic for treatment. This helps in selecting an antibiotic that the bacteria are sensitive to, ensuring the treatment is effective and reducing the risk of antibiotic resistance.

Bactericidal antibiotics vs. Bacteriostatic antibiotics.

Bactericidal antibiotics: These antibiotics kill bacteria directly. They are often used in situations where the immune system is compromised or the infection is severe.

Bacteriostatic antibiotics: These antibiotics inhibit the growth and reproduction of bacteria, allowing the immune system to eliminate the pathogens. They are used when the immune system can effectively control and eradicate the infection.

Broad spectrum vs. narrow spectrum antibiotics

Broad spectrum antibiotics: These antibiotics are effective against a wide range of bacteria, both gram-positive and gram-negative. They are useful when the specific bacteria causing the infection are unknown, but they can also disrupt the normal microbiota and lead to resistance.

Narrow spectrum antibiotics: These antibiotics target specific types of bacteria. They are preferred when the causative bacteria are known, as they minimize disruption to the normal microbiota and reduce the risk of developing antibiotic resistance.

Explain the steps in how bacteria may become resistant to a certain antibiotic.

A population of bacteria includes both susceptible and naturally resistant bacteria.

When an antibiotic is used, it kills the susceptible bacteria.

The resistant bacteria survive the antibiotic treatment.

The resistant bacteria reproduce, passing on their resistance genes to their offspring.

Over time, the resistant bacteria become more common, and the antibiotic becomes less effective.

Why is the overuse of antibiotics a contributor to antibiotic resistance?

The overuse of antibiotics contributes to antibiotic resistance because it increases the exposure of bacteria to these drugs. This frequent exposure creates selective pressure, favouring the survival and reproduction of resistant bacteria. As a result, resistant strains become more prevalent, and the effectiveness of antibiotics diminishes.

Find the meaning of “Super bug” ‘Golden Staph” and “MDR bacteria”.

Superbug: A superbug is a strain of bacteria that has become resistant to multiple antibiotics, making it very difficult to treat infections caused by these bacteria.

Golden Staph: a type of bacteria that can cause a range of illnesses.

MDR Bacteria: MDR stands for Multi-Drug Resistant bacteria. These bacteria are resistant to multiple antibiotics, making infections caused by them particularly challenging to treat

three ways in which a bacteria can change its genes.

Transduction: Resistance genes can be transferred from one germ to another via phages.

Conjugation: Resistance genes can be transferred between germs when they connect

Transformation: Resistance genes released from nearby live or dead germs can be picked up directly another germ

More accurate

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More reliable

Increase Replicates

Prepare multiple replicate plates

Standardise Procedure

Use calibrated pipettes

Standardise spreading technique

Use a template for disc placement

More valid

Controlling variable

Standardise incubation time Control temperature

Improving measurements

Replicate measurements

Standardise measurement technique:

Use calibrated tools

Increasing Sample size

More things tested

Aim

To investigate antibiotic effectiveness against common bacteria strains.

explain how a change in a bacteria’s genes can make it resistant to the effect of an antibiotic.

Germs develop new cell processes that avoid using the antibiotic's target.

Germs change or destroy the antibiotics with enzymes, proteins that break down the drug.

Germs restrict access by changing the entryways or limiting the number of entryways.

Germs change the antibiotic's target so the drugs can no longer fit and do its job.

Germs get rid of antibiotics using pumps

hypothesis

For the E. coli plates:

Control plate (no antibiotic): Bacterial growth will be observed across the entire plate Experimental plate with antibiotic discs: Zones of inhibition (areas with no bacterial growth) will be observed around the antibiotic discs that E. coli is susceptible to

For the S. epidermidis plates: 

Control plate (no antibiotic): Bacterial growth will be observed across the entire plate Experimental plate with antibiotic discs: Zones of inhibition will be observed around the antibiotic discs that S. epidermidis is susceptible to, which may differ from E. coli

accuracy, validity, accuracy

the closeness of a measured value to a standard or known value; how accurately a method measures what it is intended to measure; The extent to which the findings of repeated experiments, conducted under identical or similar conditions, agree with each other.