Biology question help please :)

Myth

Myth

Myth

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27 Nov 2004
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122
Right, I've got this question for a lab report but I don't understand the question fully as I think that I am missing things. I don't know if anyone here can help.

Here is the question;

One unit of an enzyme is defined here as that amount which will liberate 1nano mol of product per min at 37c and pH 7 in a particular reaction mixture. Given an enzyme solution containing 20 units per ml, determine what volume must be added to an assay mixture to produce 3mg of product if the assay is carried out at 37c and pH 7 for 15min. Molecular weight of product is 200 and the reaction is constant for 15 min.

Any help would be grateful as I'm really stuck.

Thanks
 
You know there was a time long ago during my A levels when I could probably have helped.... those memories are long lost to history sadly :(
 
So I have worked out so far that I need to change the nano mol into mg

So I have done 1x200(molecular weight) =200nano g

Next 200 / 100 to change to mg = .200mg per 1 unit

The 0.2 (1 unit weight)x 20 (units per ml) = 4mg

So therefore 3 / 4 to make 3mg of product = 0.75ml
 
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Myth said:
So I have worked out so far that I need to change the nano mol into mg

So I have done 1x200(molecular weight) =200nano g

Next 200 / 100 to change to mg = .200mg per 1 unit

The 0.2 (1 unit weight)x 20 (units per ml) = 4mg

So therefore 3 / 4 to make 3mg of product = 0.75ml
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Yep, match up your units first, so work out how many mg / min of product you get with a molecular weight of 200.
1 nmol (@200 MW) = x.xxxx mg / min
1 ml of solution contains 20 units of enzyme, which makes y.yyy mg / ml / min
In 15 minutes this will make y.yyy X 15 min = z.zz mg / ml / 15 min

then work out from z.zz how many ml you need need to make 3 mg.

I get 50 ml.
 
I cant help with the problem, but if you want some free marks, start you answer with "The surface area to volume ratio of the enzyme substrate complex..." That always gets you marks in biology
 
rangor gubbins said:
Yep, match up your units first, so work out how many mg / min of product you get with a molecular weight of 200.
1 nmol (@200 MW) = x.xxxx mg / min
1 ml of solution contains 20 units of enzyme, which makes y.yyy mg / ml / min
In 15 minutes this will make y.yyy X 15 min = z.zz mg / ml / 15 min

then work out from z.zz how many ml you need need to make 3 mg.

I get 50 ml.
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I also got 50ml
 
Theophany said:
I think we should have a homework subforum. All these half term threads are killing my GD mellow.
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Theophany said:
^^ It's whiskey night tonight, vodka and trolling GD are Saturday's work. ;)
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Theopany, ignore these people with their homework and answer a more noobish but more relevant question (ironic seeing how much help I've asked of you :p ):

Is a brandy balloon glass suitable as a gift for someone who drinks a lot of whiskey? (It's for my GF who drinks almost as much as I do).

980PXkt.png



Or is it a real rookier error?
 
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I'm a little confused how you get 50ml.

It makes 1nmol per minute. So 15nmol in that 15 mins.

To make 20 nmols uses 1ml of liquid so surely the answer will be less than 1? Unless I'm missing something.
 
sports_brah said:
Theopany, ignore these people with their homework and answer a more noobish but more relevant question (ironic seeing how much help I've asked of you :p ):

Is a brandy balloon glass suitable as a gift for someone who drinks a lot of whiskey? (It's for my GF who drinks almost as much as I do).

http://i.imgur.com/980PXkt.png[IMG]


Or is it a real rookier error?[/QUOTE]

Personally, I'd go for a solid tumbler style glass instead. Snifters are really brandy only (imo - happy to be corrected) so that you can roll it around in the glass and maximise the nose on it. :)

Also, quit bragging about having a whiskey drinking girlfriend, you *******. I'm so not jealous! :p
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Theophany said:
Personally, I'd go for a solid tumbler style glass instead. Snifters are really brandy only (imo - happy to be corrected) so that you can roll it around in the glass and maximise the nose on it. :)

Also, quit bragging about having a whiskey drinking girlfriend, you *******. I'm so not jealous! :p
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Ah ******.

Still, I'm chuffed as I just won the auction for them at only 35£! Lovely brand new Waterford Crystal.

I'm reckoning I supply the glasses, she brings the Jamesons.

I'd introduce you to, but I'd reckon you'd try and steal her you delinquent you. :p

P.s I haven't forgotten I owe you drinks. ;)
 
It's 50ml.

Product weighs 200g/mol you need 3mg, so work out what proportion of a mole 3mg is, 0.003g/200g = 0.000015 . To work out how many moles you need to produce per minute divide by 15, 0.000015 mol / 15 = 1,000 nmol. One ml produces 20 nmol/min. Divide 1,000 nmol by 20 nmol and you get 50.
 
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sports_brah said:
Ah ******.

Still, I'm chuffed as I just won the auction for them at only 35£! Lovely brand new Waterford Crystal.

I'm reckoning I supply the glasses, she brings the Jamesons.

I'd introduce you to, but I'd reckon you'd try and steal her you delinquent you. :p

P.s I haven't forgotten I owe you drinks. ;)
Click to expand...

Ahaha! Seems like a fair trade to me! :p

And I shall be claiming those drinks at a date to yet be decided...
 
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