Core Practical: Investigating antibiotics & antiseptics (Edexcel GCSE Biology Combined Science): Quizzes
📚Quizzes
Practise the questions
10 questions from this quiz
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Practise the questions
10 questions from this quiz
How are glass Petri dishes and agar gel sterilised for this practical?
How are glass Petri dishes and agar gel sterilised for this practical?
In an autoclave
What is the purpose of the agar in the Petri dish?
What is the purpose of the agar in the Petri dish?
Provides a nutrient-rich environment
Why is a sterile spreader used to spread the bacterial solution?
Why is a sterile spreader used to spread the bacterial solution?
To create a uniform bacterial lawn
Why are the Petri dishes stored upside down?
Why are the Petri dishes stored upside down?
Stops condensation contaminating culture
What is the maximum temperature for incubating plates in schools?
What is the maximum temperature for incubating plates in schools?
25°C
Why are plates not fully sealed with tape?
Why are plates not fully sealed with tape?
To allow oxygen in
What are the filter paper disks soaked in?
What are the filter paper disks soaked in?
Antibiotics, antiseptics or extracts
What is the zone of inhibition?
What is the zone of inhibition?
Clear area where bacteria can't grow
What does a larger zone of inhibition indicate?
What does a larger zone of inhibition indicate?
More effective antimicrobial agent
What is the purpose of the control disk?
What is the purpose of the control disk?
To ensure accurate comparisons