AQA GCSE Biology Unit 3 - BLY3H - Monday 21st May 2012

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Scientists involved and their important developments in 'biogenesis':

Spallanzani- found boiling microbes killed them

Schwann- observed yeast and the fermentation process

Pasteur- invented pasteurisation process, where heating killed most of the bacteria in milk

Reply 181

AngryBirds4

Would somebody mind explaining how beer and wine is made, so I can be sure I'm right? Thanks :smile:

This was posted from The Student Room's iPhone/iPad App

Reply 182

Swords N Thorns

Original post by Revision-

It is the hidden part of the specification, they may include it 2moz (element of surprise),
P.S, I think they will include batch/continuous generators and/or scientists involved in biogenesis...

Ahh right...that's not good :s-smilie:

But yeah, I'm betting on something about the generators and scientists coming up too, along with something about beer/cheese production...there'll probably also be a question about exercising and how the body keeps up with it etc, since that seems to have become a trend over the years.

Reply 183

pokings

Original post by Revision-

Uniform Mark Scheme; the points that are converted from marks used to calculate the grade which you can get.

I need 78 in B3 for an A!!!

Thankyou, the complete thing is out of 400 right?

Reply 184

Sara_A

Original post by AngryBirds4

Thank you

I got 35 marks (I had to deduct 4 marks as something was removed for copyright, and so I couldn't finish it)...

I guessed a lot of it... It goes to show what it's worth not leaving anything blank and taking logical guesses :smile:

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Your welcome

Reply 185

Sara_A

Can someone explain how beer is made and how wine is made into simple steps thanks :biggrin:

Reply 186

Jack_Smith

Original post by James3110

Here you go :smile:

Do you have the Jan 2012 paper by any chance? Thanks

Reply 187

Revision-

Original post by pokings

Thankyou, the complete thing is out of 400 right?

yup, 360= A*
320= A
280= B

Reply 188

Swords N Thorns

Original post by AngryBirds4

Would somebody mind explaining how beer and wine is made, so I can be sure I'm right? Thanks :smile:

This was posted from The Student Room's iPhone/iPad App

Beer:
Starch in barley grains is broken down into simple sugars by enzymes in germinating grains in a process called malting.
Simple sugars are then extracted and fermented.
Hops are added to give beer its bitter flavour.

I'm pretty sure that malting isn't a part of wine-making as it uses the natural sugars in the grapes, or something.

I've got:
Grapes and picked and washed before being squashed to extract the juices.
Grape juice mixture added to water and yeast.
Anaerobic respiration occurs, using natural sugars from the fruit, producing alcohol.
Wine filtered to remove yeast.
Wine bottled and left to mature.

Hope it helped a little!

Reply 189

OllieWolly

Original post by steviep14

Cheese is NOT on the B3 Specification.
Beer, Yoghurt and Wine are the three main ones.
You also need to know CO2 causes the Bread to Rise

Cheese is definitely in the specification :s-smilie:

Here:
http://store.aqa.org.uk/qual/pdf/AQA-4411-W-SP-12.PDF

Check on page 52 - Microorganisms are used to make food and drink: − bacteria are used in yoghurt and cheese manufacture − yeast is used in making bread and alcoholic drinks

Reply 190

Kutal

Original post by AngryBirds4

Would somebody mind explaining how beer and wine is made, so I can be sure I'm right? Thanks :smile:

This was posted from The Student Room's iPhone/iPad App

Right beer: Barley grains are soaked in water and left to Germinate. Enzymes in the grains break down the starch into glucose. This glucose is then used to anaerobically ferment yeast producing alcohol.

Wine is similar but instead of malting (using barley grains) you just use natural sources of sugar such as grapes which are squeezed, mixed with water and yeast. This is left to anaerobically respire and the yeast is filtered off to produce wine.

(edited 11 years ago)

Reply 191

amber206

Is:
ISA 25%
B1 25%
B2 25%
B3 25%

? :smile:

Reply 192

Sara_A

Can someone also explain why a water cooled jacket is used for the fermenter? thanks

Reply 193

James3110

Original post by Jack_Smith

Do you have the Jan 2012 paper by any chance? Thanks

Oops sorry I didn't see your earlier post when you asked for it :colondollar:

AQA-BLY3H-QP-Jan12.pdf285.2KB

Reply 194

Jack_Smith

Original post by James3110

Oops sorry I didn't see your earlier post when you asked for it :colondollar:

Thank you so much! :smile:

Reply 195

amber206

Original post by Sara_A

Can someone also explain why a water cooled jacket is used for the fermenter? thanks

It takes away heat so that the enzymes of the microbes don't denature, as they would if the temperature got too high

Reply 196

Sara_A

Whats sort of questions can come up related to exercising? thanks

Reply 197

Kutal

Original post by Sara_A

Can someone also explain why a water cooled jacket is used for the fermenter? thanks

Microorganisms in the fermenter will respire which produces heat. The jacket is used to maintain a stable temperature so that it does not get too hot for things such as enzymes to denature.

Reply 198

Swords N Thorns

Original post by Sara_A

Can someone also explain why a water cooled jacket is used for the fermenter? thanks

Microorganisms release heat/energy as a product of respiration, so a water-cooled jacket allows the fermenter to maintain an optimum temperature to prevent the denaturing of enzymes. :smile:

(edited 11 years ago)

Reply 199

PoorLoser

I'm stuck on this question if anyone can help me out I will greatly appreciate it - I know the answer just not how to work it out:

May 2010
Biology 3
Question 1 b iii

Thanks a lot