Here's an FAQ on what you should do in terms of preparing for the proteins section for Chem H2 syllabus. What do you need to study??
I suggest you print this FAQ and append to your tutorial 14b. The FAQ also references tutorial 14b.
Q1. Is it important to know about how enzymes work (induced fit theory etc.)?
A1. No. However students must know that enzyme function depends on its structure, which means if the structure is lost through denaturation, function is lost too. The whole chunk about how enzymes work explains the structure function relationship.
Q2. So what is it that the students NEED to know?
A2. The tutorial is crafted according to SIOs of the syllabus. So its a good guide on what students need to know. Basically 4 major portions:
i) amides - hydrolysis, synthesis, and peptide sequencing. That’s tutorial qn 1,2,3
ii) Protein stucture - Mostly fact and recall. Definitions and esp FOCUS ON BONDING
involved. They also need to draw diagrams, which cannot be only memorized but must be practiced (to draw good diagrams) esp for secondary and tertiary. Tutorial Q4,5,6,10
Quaternary structure. Question 10: you notice there are only 6 marks awarded but 12 bullets in the answer key! Why?
Actually on the FIRST 6 bullets in the answer key are marking points. Those points give a DESCRIPTION of what the quaternary structure is.
The next 6 bullet points actually give the SIGNIFICANCE of the quaternary structure. SO students need to discern; the points from allosteric properties onward should be written if the question asks for SIGNIFICANCE of quaternary structure.
The specific use of haemoglobin as an example is an SIO. So students must know all these points.
iii) Denaturation - Students should know the process, how denaturation take place. They should also know the significance and explain: mainly loss of normal function such as structural strength(eg in rebonding) or catalytic property(rate of enzyme catalysed reactions) and solubility(coagulation). Tutorial questions 7,8,9
iv) Explaining observed phenomenon: examples are given in notes from pg44-45. They need to know them for experience. The examples are by no means exhaustive, and I do not know what's going to feature in the A lvls. The basic concept is that structural alteration(usually via denaturation)or structural differences alters observed function. So students should be exposed and familiar with as many examples as possible, and be able to explain when given any example. Tutorial Q7,8,9
Q3. What does allosteric properties mean?
A3. It means that the biochemical property of the protein is altered. If this word makes you feel uncomfortable feel free to expand. It should go something like "The significance of the quaternary structure is that the biochemical properties of the protein is changed; allosteric properties can arise in the quarternary complex."
A little bit more about allosteric properties: it has to do with altering enzyme active site property when something else binds to it at some other site other than its own active site.
So the haemoglobin example illustrates this... the haemoglobin sub-units are bound together by extensive side chain interaction, when an oxygen molecule bonds to one of the haem groups, its subunit's conformation alters. This forces a conformational change on the other subunits. The result is that their haem groups now have an increased tendency to bind oxygen.
For bio students you would have seen other egs of allosteric effects, eg from co-factors, co-enzymes, and allosteric inhibitors
I suggest you print this FAQ and append to your tutorial 14b. The FAQ also references tutorial 14b.
Q1. Is it important to know about how enzymes work (induced fit theory etc.)?
A1. No. However students must know that enzyme function depends on its structure, which means if the structure is lost through denaturation, function is lost too. The whole chunk about how enzymes work explains the structure function relationship.
Q2. So what is it that the students NEED to know?
A2. The tutorial is crafted according to SIOs of the syllabus. So its a good guide on what students need to know. Basically 4 major portions:
i) amides - hydrolysis, synthesis, and peptide sequencing. That’s tutorial qn 1,2,3
ii) Protein stucture - Mostly fact and recall. Definitions and esp FOCUS ON BONDING
involved. They also need to draw diagrams, which cannot be only memorized but must be practiced (to draw good diagrams) esp for secondary and tertiary. Tutorial Q4,5,6,10
Quaternary structure. Question 10: you notice there are only 6 marks awarded but 12 bullets in the answer key! Why?
Actually on the FIRST 6 bullets in the answer key are marking points. Those points give a DESCRIPTION of what the quaternary structure is.
The next 6 bullet points actually give the SIGNIFICANCE of the quaternary structure. SO students need to discern; the points from allosteric properties onward should be written if the question asks for SIGNIFICANCE of quaternary structure.
The specific use of haemoglobin as an example is an SIO. So students must know all these points.
iii) Denaturation - Students should know the process, how denaturation take place. They should also know the significance and explain: mainly loss of normal function such as structural strength(eg in rebonding) or catalytic property(rate of enzyme catalysed reactions) and solubility(coagulation). Tutorial questions 7,8,9
iv) Explaining observed phenomenon: examples are given in notes from pg44-45. They need to know them for experience. The examples are by no means exhaustive, and I do not know what's going to feature in the A lvls. The basic concept is that structural alteration(usually via denaturation)or structural differences alters observed function. So students should be exposed and familiar with as many examples as possible, and be able to explain when given any example. Tutorial Q7,8,9
Q3. What does allosteric properties mean?
A3. It means that the biochemical property of the protein is altered. If this word makes you feel uncomfortable feel free to expand. It should go something like "The significance of the quaternary structure is that the biochemical properties of the protein is changed; allosteric properties can arise in the quarternary complex."
A little bit more about allosteric properties: it has to do with altering enzyme active site property when something else binds to it at some other site other than its own active site.
So the haemoglobin example illustrates this... the haemoglobin sub-units are bound together by extensive side chain interaction, when an oxygen molecule bonds to one of the haem groups, its subunit's conformation alters. This forces a conformational change on the other subunits. The result is that their haem groups now have an increased tendency to bind oxygen.
For bio students you would have seen other egs of allosteric effects, eg from co-factors, co-enzymes, and allosteric inhibitors
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