Photo AI
Many living cells produce hydrogen peroxide as a by-product of some metabolic reactions - VCE - SSCE Biology - Question 3 - 2007 - Paper 1
Question 3
Many living cells produce hydrogen peroxide as a by-product of some metabolic reactions. Hydrogen peroxide is a poisonous substance for these cells and is immediatel... show full transcript
Worked Solution & Example Answer:Many living cells produce hydrogen peroxide as a by-product of some metabolic reactions - VCE - SSCE Biology - Question 3 - 2007 - Paper 1
Step 1
Step 2
b. Do you agree or disagree with the student's prediction? Explain the reason for your choice.
Answer
I agree with the student's prediction. As carrot plants typically grow in a soil temperature around 16°C, it can be expected that the optimal catalase activity temperature for carrots would be lower than the human optimal temperature of 37°C. This disparity arises due to the environmental adaptations of the plant. As temperatures increase beyond the optimal range, the enzyme activity could decrease due to denaturation.
Step 3
c. Describe (or outline) an experiment you would carry out with pieces of carrot to test the accuracy of the student's prediction. Hydrogen peroxide is available as a 3% in water solution. Explain fully what results would support or negate the student's prediction.
Answer
To test the student's prediction, I would prepare an experiment using pieces of carrot as a source of catalase. I would set up several test tubes containing equal amounts of 3% hydrogen peroxide solution and carrot pieces. Heat each test tube to different temperatures, ranging from 0°C to 50°C, and measure the amount of oxygen produced over a set time. The results that would support the student's prediction would be higher oxygen production at lower temperatures (around 16°C), indicating optimal catalase activity, and decreased production at higher temperatures. If the optimal activity were found to be significantly higher than 16°C, it would negate the student's prediction.