Defence against disease - antibiotic resistance Flashcards
What causes variation within a bacterial population?
Mutations
Variation is a natural occurrence in populations of all species, leading to genetic diversity.
What happens when a chance mutation causes some bacteria to become resistant to an antibiotic?
Resistant bacteria do not die when treated with the antibiotic
This allows them to reproduce while non-resistant bacteria die.
How do resistant bacteria affect the reproduction of their population?
They can reproduce with less competition from non-resistant bacteria
This leads to the propagation of antibiotic resistance genes.
Why do genes for antibiotic resistance get passed on with greater frequency?
Because resistant bacteria survive and reproduce more than non-resistant bacteria
This is a key mechanism in natural selection.
What is the immediate effect of a mutant gene in bacteria?
It has an immediate effect on any bacterium possessing it
Bacteria have only one copy of each gene.
What is the overall outcome of antibiotic resistance in bacterial populations over time?
The whole population becomes antibiotic-resistant
This occurs because the resistant bacteria are better suited to their environment.
What enzyme do some pathogenic bacteria produce to resist penicillin?
β-lactamase (penicillinase)
This enzyme breaks down penicillin, rendering it ineffective.
What are some major problems posed by antibiotic-resistant strains?
They create infections and diseases that are very difficult to treat
Methicillin-resistant Staphylococcus aureus (MRSA) is a notable example.
What contributes to the emergence of new antibiotic-resistant strains?
The overuse of antibiotics
This exerts selective pressure on bacteria, promoting resistance.
What measures can help to avoid antibiotic resistance?
Avoiding unnecessary prescriptions, maintaining hygiene, minimising agricultural antibiotic use, and developing new antibiotics
Each measure targets different aspects of antibiotic use and resistance.
What is a top priority for the World Health Organization (WHO)?
Addressing antibiotic resistance
This is vital for ensuring effective treatment of common infections.
What is currently being done to develop new antibiotics?
Researchers are using chemical libraries to craft and produce fresh antibiotics
These libraries contain numerous chemical compounds with antibacterial characteristics.
Fill in the blank: The rise of antibiotic resistance presents significant challenges within the _______.
[medical field]
It complicates treatment and increases mortality rates.
True or False: Antibiotic resistance is solely a result of bacterial mutations.
False
Human actions, such as the overuse of antibiotics, also play a critical role.
