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Evolution by natural selection is more rapid in prokaryotes than eukaryotes - Scottish Highers Biology - Question 3 - 2022
Question 3
Evolution by natural selection is more rapid in prokaryotes than eukaryotes. Staphylococcus aureus is a species of bacteria that causes infections in humans. A stra... show full transcript
Worked Solution & Example Answer:Evolution by natural selection is more rapid in prokaryotes than eukaryotes - Scottish Highers Biology - Question 3 - 2022
Step 1
Explain why evolution by natural selection is more rapid in prokaryotes.
Answer
Evolution by natural selection is more rapid in prokaryotes because they can carry out horizontal transfer of genes or DNA. Unlike eukaryotes, prokaryotes can rapidly exchange genetic material between individuals in the same generation, allowing for quicker adaptation to environmental pressures such as antibiotics.
Step 2
Use your knowledge of natural selection to explain how the use of antibiotics has led to the evolution of MRSA.
Answer
The use of antibiotics creates a selective pressure where only MRSA, the resistant bacteria, are able to survive and reproduce. Non-resistant bacteria are inhibited or killed. The surviving MRSA pass on their advantageous resistance genes to their offspring, leading to a population that is increasingly resistant to antibiotics.
Step 3
Describe the overall trend in the number of deaths caused by MRSA and non-resistant Staphylococcus aureus infections from 2005 to 2016.
Answer
MRSA: The overall trend shows an increase in deaths caused by MRSA up until 2007 when it peaked, followed by a decrease in subsequent years.
Non-resistant Staphylococcus aureus: The number of deaths caused by non-resistant Staphylococcus aureus remained fairly constant over the years, with minor fluctuations.
Step 4
Control measures were introduced in hospitals to reduce the spread of MRSA. Using information from the table, suggest a year that these measures may have been introduced.
Answer
Control measures may have been introduced around 2008 or 2009, as evidenced by a notable decrease in deaths caused by MRSA after 2007.
Step 5