Biology 9700 · AS & A Level · Testing for biological molecules

Testing for biological molecules — practice question

The iodine test and Benedict’s test were performed on samples of a starch solution. Amylase was added to another sample of the starch solution, which was then incubated for $10$ minutes. After this, the Benedict’s test was done on this sample. What were the outcomes of the tests?

  • AIodine test before adding amylase: $\times$; Benedict’s test before adding amylase: $\checkmark$; Benedict’s test after adding amylase: $\checkmark$
  • BIodine test before adding amylase: $\checkmark$; Benedict’s test before adding amylase: $\checkmark$; Benedict’s test after adding amylase: $\times$
  • CIodine test before adding amylase: $\checkmark$; Benedict’s test before adding amylase: $\times$; Benedict’s test after adding amylase: $\checkmark$
  • DIodine test before adding amylase: $\times$; Benedict’s test before adding amylase: $\times$; Benedict’s test after adding amylase: $\times$

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