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Streptococcus mutans is one species of bacteria which causes tooth decay - Edexcel - GCSE Biology - Question 4 - 2021 - Paper 1
Question 4
Streptococcus mutans is one species of bacteria which causes tooth decay. A scientist tested the effectiveness of toothpaste at killing this species of bacteria. T... show full transcript
Worked Solution & Example Answer:Streptococcus mutans is one species of bacteria which causes tooth decay - Edexcel - GCSE Biology - Question 4 - 2021 - Paper 1
Step 1
Which word describes the techniques used to prevent contamination of the agar jelly plate?
Answer
The correct answer is C: aseptic. Aseptic techniques are essential in microbiological procedures to prevent unwanted contamination of cultures. Clinical and diagnostic are not proper descriptions of such techniques, and lysogenic refers to a phase in a virus's life cycle rather than contamination methods.
Step 2
Give two precautions needed to prevent contamination of the agar jelly plate.
Answer
To prevent contamination of the agar jelly plate, the following precautions should be taken:
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Keep the lid on at all possible times to minimize exposure to airborne contaminants.
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Use sterile equipment, such as flaming loops or disinfecting the working area, to eliminate potential contaminants.