Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 353903 times)

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1605 on: May 23, 2010, 03:30:32 pm »
Could someone please help me with the following question:

BIO P3:

1) nov 2007 no. 4c
2) jun 2007 no. 4ii (diff between source and sink?)
3) jun 2006 no. 5c
4) nov 2005 no. 6c
5) quorn vs. mycoprotein...which one is produced by bacteria and which one's produced by fungus?

Sorry for all my question!

1) Vasoconstriction is the answer. This is when the capillaries near the surface of the skin gets narrower so that less heat is lost.
2)Source is the place where a particular substance is obtained from. Sink is the final destination of tht substance.
3)No it isn't genetic enginnering as tht is taking a DIFFERENT gene from an organism and placing it in another organism. Here they just wants to make the gene more active. (I am not sure of this ans check with the MS :P )
    
;D

Offline NidZ- Hero

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1606 on: May 23, 2010, 03:30:39 pm »
yep..it took a load off my mind :)
but hey go do de pastppr n u vil find question abut it once i dunt remember de year but it sureli did cum  :) ;D

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1607 on: May 23, 2010, 03:31:58 pm »
I'm pretty sure we don't need to know anything about the brain (except for the fact that it's part of the central nervous system with the spinal cord)? Unless you're taking O-Level, which you're not, as far as I know?

OH.. r u serious we dont need to learn this for Igcse? OMG... i didnt know tht.. :O
;D

Offline NidZ- Hero

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1608 on: May 23, 2010, 03:34:56 pm »
I'll give you an example of phases in bacterial growth.

Lag phase:  When doubling of the numbers has little effect as the numbers are so small.  Bacteria take up water and nutrients, make new cytoplasm, DNA and enzymes.

Log phase:  When the population is increasing rapidly.  The populatoin increases by doubling and there are no limiting factors, such as food or water.

Stationary phase:  When bacterial cells are dying at the same rate at which they are being produced.  This may be because of shortage of food or because waste products are building up.

Death phase:  When more cells are dying than are being produced, so the population declines.  Causes of death may be lack of food, shortage of oxygen or a build-up of toxic waster products.

Hope that helps!
hey but still wats de difference btwen lag n log can u plz explain ???:)

Offline Moonlyte

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1609 on: May 23, 2010, 03:35:36 pm »
1) Vasoconstriction is the answer. This is when the capillaries near the surface of the skin gets narrower so that less heat is lost.
2)Source is the place where a particular substance is obtained from. Sink is the final destination of tht substance.
3)No it isn't genetic enginnering as tht is taking a DIFFERENT gene from an organism and placing it in another organism. Here they just wants to make the gene more active. (I am not sure of this ans check with the MS :P )
    

Thank you VERYYY much!!!!!

Offline saleemsamer

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1610 on: May 23, 2010, 03:37:07 pm »
Hey guys
i kno i have mark schemes but can some1 plz give me a model answer for O/N 05 p3 q6 c (biology) PLZ
it says ref. and ref. i kno wat it means but i wud like a full answer
thx in advance :)

Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1611 on: May 23, 2010, 03:38:42 pm »
please explain following question......
chemistry paper 2......M/J/07

section A
Q7 part C

section B
Q11 part D

B11D

PROPANOL+ OXIDIZING AGENT =       PROPANOIC ACID + WATER
propanol + 2 [O] = C3H7OH + 2 [O] = CH3CH2COOH + H2O

A7C - im not sure, wait for nid..
divine intervention!

Offline Moonlyte

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1612 on: May 23, 2010, 03:40:17 pm »
hey but still wats de difference btwen lag n log can u plz explain ???:)


lag phase: Initially, the increase is slow because we start with only few organisms. The rise is gentle as there are few reproducing individuals. Besides the population density being low, organisms are adapting to the environment.

log phase: the organisms have estavlished themselves and growth rate has become rapid. The population increases at an exponential/logarithmic rate. Birth rate exceed death rate, There are no limiting factors as food and space is in abundance. The population grows at its maximum potential rate, doubling in size every generation.

Offline Burhan.arshad

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1613 on: May 23, 2010, 03:41:14 pm »
B11D

PROPANOL+ OXIDIZING AGENT =       PROPANOIC ACID + WATER
propanol + 2
  • = C3H7OH + 2
  • = CH3CH2COOH + H2O


A7C - im not sure, wait for nid..


Thanks
« Last Edit: May 23, 2010, 03:43:12 pm by A@di »
I hAve sEEn mAny prEty wOmEns bUt nO prEfEct OnEs

Offline Moonlyte

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1614 on: May 23, 2010, 03:41:24 pm »
Hey guys
i kno i have mark schemes but can some1 plz give me a model answer for O/N 05 p3 q6 c (biology) PLZ
it says ref. and ref. i kno wat it means but i wud like a full answer
thx in advance :)

i have the same question

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1615 on: May 23, 2010, 03:42:58 pm »
lol, no we don't need to know all the functions and stuff ;) it's not mentioned anywhere in the syllabus, i'm 1000000% sure.

should be easier for you now!

good luck :) i'm sure you'll do well

Hahah.. well im glad all of them aren't there.. :)
;D

Offline Helium

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1616 on: May 23, 2010, 03:43:56 pm »
Could someone please help me with the following question:

BIO P3:

1) nov 2007 no. 4c
2) jun 2007 no. 4ii (diff between source and sink?)
3) jun 2006 no. 5c
4) nov 2005 no. 6c
5) quorn vs. mycoprotein...which one is produced by bacteria and which one's produced by fungus?

Sorry for all my question!

I was just solving 07 and 06
For your first Question

1)They want want the place where the diameter is reduced, How and why
I said Just after the stomach the diameter is reduced by sphincter muscles so food can be digested then passed
on the doudenum. (hope i'm correct, yes i know its sounds wierd vasconstriction is better, comment anyone)

2)Have no idea and want to know :-\

3)Have a anwser but want to hear it from someone else
Q:An article in a school science magazine stated, ‘Many plants contain genes which
enable them to pump salts out of their roots. These genes can be made more active by
genetic engineering, enabling the plants to remove salts before the plants are damaged.’
Explain whether you think that the process described in the article above is an example
of genetic engineering.

4)Outline how enzymes can be manufactured for use in biological washing powders.


5) quorn is produced by bacteria, mycroprotien from fungus
yes i was useless lol ;D


Aiming for the top

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1617 on: May 23, 2010, 03:44:57 pm »
Thank you VERYYY much!!!!!

No problem.. :)
;D

Offline Moonlyte

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1618 on: May 23, 2010, 03:47:41 pm »
I was just solving 07 and 06
For your first Question

1)They want want the place where the diameter is reduced, How and why
I said Just after the stomach the diameter is reduced by sphincter muscles so food can be digested then passed
on the doudenum. (hope i'm correct, yes i know its sounds wierd vasconstriction is better, comment anyone)

2)Have no idea and want to know :-\

3)Have a anwser but want to hear it from someone else
Q:An article in a school science magazine stated, ‘Many plants contain genes which
enable them to pump salts out of their roots. These genes can be made more active by
genetic engineering, enabling the plants to remove salts before the plants are damaged.’
Explain whether you think that the process described in the article above is an example
of genetic engineering.

4)Outline how enzymes can be manufactured for use in biological washing powders.


5) quorn is produced by bacteria, mycroprotien from fungus
yes i was useless lol ;D





thanks! you were not useless, but very helpful...for no. 3, check your ans by the ans given by Raywin: "No it isn't genetic enginnering as tht is taking a DIFFERENT gene from an organism and placing it in another organism. Here they just wants to make the gene more active."
and i guess its right. 

Offline Moonlyte

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1619 on: May 23, 2010, 03:49:10 pm »
I was just solving 07 and 06
For your first Question

1)They want want the place where the diameter is reduced, How and why
I said Just after the stomach the diameter is reduced by sphincter muscles so food can be digested then passed
on the doudenum. (hope i'm correct, yes i know its sounds wierd vasconstriction is better, comment anyone)

2)Have no idea and want to know :-\

3)Have a anwser but want to hear it from someone else
Q:An article in a school science magazine stated, ‘Many plants contain genes which
enable them to pump salts out of their roots. These genes can be made more active by
genetic engineering, enabling the plants to remove salts before the plants are damaged.’
Explain whether you think that the process described in the article above is an example
of genetic engineering.

4)Outline how enzymes can be manufactured for use in biological washing powders.


5) quorn is produced by bacteria, mycroprotien from fungus
yes i was useless lol ;D




and also the second one the answer was given by Raywin: "Source is the place where a particular substance is obtained from. Sink is the final destination of tht substance."