Interactive Resources for Schools
This topic takes on average 55 minutes to read.
There are a number of interactive features in this resource:
Biology
Chemistry
PSHE / Citizenship studies
Science
Microorganisms are gaining resistance to antimicrobialantimicrobial
A group of medicines including antibiotics, anti-viral and anti-fungal medicines. These are used to treat infections by bacteria, viruses, fungi, and parasites.
s - this is called antimicrobial resistanceantimicrobial resistance
The ability of a micro-organism to grow or survive in the presence of an antimicrobial at a concentration that is usually sufficient to inhibit or kill micro-organisms of the same species.
. This is often also called antibioticantibiotic
Medicine that is used to treat bacterial infections and works by killing or stopping the growth and reproduction of bacteria. These can be specific to a particular bacteria or act on groups of related bacteria.
resistance.
Microorganisms mutate in a random process called genetic driftgenetic drift
The change in the frequency of existing alleles over time due to random chance. It can lead to the fixation or loss of alleles in a population.
. These mutationmutation
A change in the arrangement or amount of genetic material in a cell.
s create microorganisms with a range of phenotypephenotype
Set of observable traits of an organism. It is determined by the combination of an organism’s complete set of genetic material, or genotype, and the environment.
s. Some of these microorganisms will be resistant to antimicrobialsantimicrobials
A group of medicines including antibiotics, anti-viral and anti-fungal medicines. These are used to treat infections by bacteria, viruses, fungi, and parasites.
.
Natural selectionnatural selection
The process in nature where the fittest individuals survive, reproduce and pass their characteristics on to their offspring.
occurs when antimicrobials are used; antimicrobial medicines act as a selection pressureselection pressure
Event(s) which affects the ability of an organism to survive in its environment.
. Only resistant microbesmicrobes
Group of organisms of microscopic size that can be found in a single cell form or forming multicellular colonies. Most microbes are found in the domains of archaea and bacteria, but there are also some eukaryotes.
can survive and reproduce. These microorganisms will pass on their resistance to offspring, passing on their selective advantage.
The diagram below summarises the development of antimicrobial or antibiotic resistance.
Once a microbe has developed resistance, it can pass it on to its offspring. Alternatively, bacteriabacteria
Single-celled organism. Has a cell wall, cell membrane, cytoplasm. Its DNA is loosely-coiled in the cytoplasm and there is no distinct nucleus.
can share plasmidplasmid
A piece of genetic material in a cell. Normally a small, circular strand of DNA, which is independent of the main genetic material of the organism.
s that code for antibioticantibiotic
Medicine that is used to treat bacterial infections and works by killing or stopping the growth and reproduction of bacteria. These can be specific to a particular bacteria or act on groups of related bacteria.
resistance between each other via conjugationconjugation
Parasexual mode of reproduction of bacteria in which there is a transfer of genetic material between bacterial cells by direct cell-to-cell contact. This is done through a pilus that attaches the cells to each other. Commonly used to transfer plasmid DNA containing resistant genes, thus spreading resistance.
.
S. aureus divides every 30 minutes. If you start with one S. aureus bacterium, it would take only 5 hours for that single cell to grow into a colony of 1,024 cells. After 5 more hours, the population size will be 1,048,576 cells.
S. aureus has approximately 2.8 million nucleotidenucleotide
Monomer unit of the nucleic acids DNA and RNA. Each nucleotide is made up of three parts: a pentose sugar, a phosphate group and a nitrogenous base.
base pairs in its genome. If the mutationmutation
A change in the arrangement or amount of genetic material in a cell.
rate were 10-10 mutations per nucleotide base there would be 300 mutations in that population of cells within 10 hours!
Antimicrobial resistance development is an example of evolution via natural selection.
What are some other examples of natural selection?
