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secondary 3 | Biology
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rosypillows
Rosypillows

secondary 3 chevron_right Biology

hi, can anyone help me with this question? thanks :))

Date Posted: 6 years ago
Views: 1528
Ashley Chen
Ashley Chen
6 years ago
Would you like to try filling it up first? Google what do proteases (it's an enzyme) do. So what would happen to the milk proteins?

What conditions would destroy your protease?

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a)
I’m not sure what format your teacher wants for word equations, but the information should convey something like this:
Milk proteins -Protease> Amino acids
Essentially the idea is that the protease digests/ breaks down the milk protein to amino acids.

bi)
Milk agar would originally be opaque because of the milk proteins. Clear zones indicate that the milk proteins have been digested/ broken down.

ii)
A: Clear zone around the hole
B: No clear zone
C: No clear zone
D: No clear zone

The question only asks you to “state”, but for your own learning I’ll explain why:
A: Protease is an enzyme that digests proteins, including milk proteins.
B: Although the protease would digest the milk proteins, the concentrated sodium hydroxide solution denatures the protease. This means that, because of the harsh chemical conditions from the sodium hydroxide solution, the protease enzyme cannot function anymore, so it cannot digest the milk proteins.
C: Similarly, boiling denatures the protease too, so it cannot digest the milk proteins.
D: Water has no effect

c)
The distilled water is to act as a negative control for the protease solution. The protease solution consists of protease and distilled water. By adding only distilled water in Hole D, we can directly compare the effect of adding a single variable, which is the protease. By doing this, we know that any difference in results between Hole A and Hole D is due to the presence of protease.
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Timothy Lim
Timothy Lim's answer
2 answers (Tutor Details)
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