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im still confused... what is high silica content?
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A level Biology: Post your doubts here!
- Thread starter XPFMember
- Start date
To summarize the entire point:
Insulin is a protein made up of two polypeptides/chains (A and B) joined by disulphide bonds and doesn't contain methionine (a specific amino acid).
Each polypeptide is synthesized from one gene, so there are two genes which code for insulin (one for each polypeptide)
After the location of the gene (that codes for insulin) is found, we add a lac operon (to each gene) along with a triplet coding for methionine.
The lac operon is pretty much a small piece of DNA with a big "Start transcription here" sign on it. In the presence of lactose, it activates, and reverse transcriptase does its job.
At the end of each gene, add a stop codon to stop transcription of cDNA from going any further.
Once reverse transcriptase finishes its work, we add cyanogen bromide. It is a chemical that cuts the gene from methionine (since we know insulin doesn't contain methionine, then it will cut the gene from the added methionine).
You now have two strands (A and B). After treatment, they will form disulphide bonds with each other, and now you have your own home made insulin
Hope that made sense!
From what I know, the endodermal cells of sorghum have a high silica content which is thought to provide drought resistance.
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Does anyone have the bio revision guide pdf to download.........plssss
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To summarize the entire point:
Insulin is a protein made up of two polypeptides/chains (A and B) joined by disulphide bonds and doesn't contain methionine (a specific amino acid).
Each polypeptide is synthesized from one gene, so there are two genes which code for insulin (one for each polypeptide)
After the location of the gene (that codes for insulin) is found, we add a lac operon (to each gene) along with a triplet coding for methionine.
The lac operon is pretty much a small piece of DNA with a big "Start transcription here" sign on it. In the presence of lactose, it activates, and reverse transcriptase does its job.
At the end of each gene, add a stop codon to stop transcription of cDNA from going any further.
Once reverse transcriptase finishes its work, we add cyanogen bromide. It is a chemical that cuts the gene from methionine (since we know insulin doesn't contain methionine, then it will cut the gene from the added methionine).
You now have two strands (A and B). After treatment, they will form disulphide bonds with each other, and now you have your own home made insulin
Hope that made sense!
THANK YOUUUU SO MUCHH! THANK YOU THANK YOU THANK YOU!
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Pencil!
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oohhhh i see!! thanks!!!!!
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Biology%20(9700)/9700_nos_as_1.pdf
http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_nos_as_2.pdf
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Biology%20(9700)/9700_nos_as_3.pdf
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Biology%20(9700)/9700_nos_as_4.pdf
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Biology%20(9700)/9700_nos_as_5.pdf
Here are 5 chapters, but I can't find the rest.
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Does anyone ever get 40/40 ?
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No matter how much good the exams go , we always end up with mistakes XD...what about those people with achievers awards don't they get a full mark?Does anyone ever get 40/40 ?
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Gosh..are you seriously saying you want "full marks"...Be happy even if you get half the full mark....
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Whaaaat is it that bad X_XGosh..are you seriously saying you want "full marks"...Be happy even if you get half the full mark....
Photorespiration is when oxygen binds with RuBP instead of carbon dioxide in the Calvin Cycle (light-independent reactions, according to the A2 book)
The light independent reactions require a lot of ATP.
When carbon dioxide enters the Calvin Cycle, the ATP (along with NADPH) is used to produce G3P (or PGAL according to the A2 book)
When oxygen enters the cycle, nothing is produced. So the ATP and NADPH is completely wasted.
An advantage of C4 plants is that they can avoid photorespiration (i.e. they prevent oxygen from binding to RuBP and only allow carbon dioxide to bind to RuBP) which saves a lot of ATP and NADPH.
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Can someone explain me this "food containing expressed products of antibiotic resistance marker genes could be consumed at the same time as treatment with the antibiotic was occuring which would potentially reduce the effectiveness of the treatment" ?