Investigating decay (AQA GCSE Biology): Quizzes
📚Quizzes
Practise the questions
12 questions from this quiz
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Practise the questions
12 questions from this quiz
What do bacteria produce when they break down organic materials during decay?
What do bacteria produce when they break down organic materials during decay?
Acids that lower pH
Why is lipase used instead of bacteria in the decay investigation?
Why is lipase used instead of bacteria in the decay investigation?
It makes the practical quicker to observe
What type of substance is lipase?
What type of substance is lipase?
An enzyme
How much milk is added to the test tube in Step 1?
How much milk is added to the test tube in Step 1?
5cm³
How much lipase solution is added to the milk mixture in Step 3?
How much lipase solution is added to the milk mixture in Step 3?
1cm³
What is the purpose of adding sodium carbonate solution at the start?
What is the purpose of adding sodium carbonate solution at the start?
To make the mixture alkaline
What colour is cresol red indicator in alkaline conditions?
What colour is cresol red indicator in alkaline conditions?
Purple
What colour does cresol red turn when acids are produced?
What colour does cresol red turn when acids are produced?
Yellow
How do higher temperatures affect the rate of decay?
How do higher temperatures affect the rate of decay?
Make decay happen faster
Why does keeping food in fridges help preserve it?
Why does keeping food in fridges help preserve it?
Lower temps slow bacteria and enzymes
What measurement is used to determine the rate of decay in this practical?
What measurement is used to determine the rate of decay in this practical?
Time for indicator colour change
What should be plotted on the horizontal axis of the results graph?
What should be plotted on the horizontal axis of the results graph?
Temperature