IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => IGCSE/ GCSE => Sciences => Topic started by: nits94 on November 01, 2009, 10:00:18 am

Title: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 10:00:18 am
A few questions I cant understand so please help me out with them.. :)
How can bacteria be genetically engineered and used to make human insulin...if u guys need ref this ques is in 2005 oct/nov paper...question5
and another 1...enzymes are used in biological washing powders this may increase the efficiency of the washing powder in removing stains from clothes so why does the temperature of the wash need to be carefully controlled??
please tell me the answers...Thanks in advance.. :)
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 10:35:38 am
Part 1 - There are two types of micro-organisms which can be used to make enzymes - fungi or bacteria. The micro-organisms are then added a fermenter [which is a large, sterile container containing a stirrer, air pipes (to blow air into the mixture) and a pipe to add feedstock]. The temperature is maintained at about 26.c and at a pH of less then neutral (about 5-6). The enzymes produced are then of two types - extracellular (which are extracted from the foodstock by filtering) and intracellular (which are basically extracellular enzymes, crushed and washed with water); the enzymes are now in solution.

Part 2 - Enzymes help in removing stains from clothes because enzymes such as proteases break down blood stains (as blood contains the protein called haemoglobin) so then this makes it easier to remove stains. Furthermore, stains made by oils can also be removed because oils are lipids so they can be broken down by lipase enzymes into fatty acids and glycerol which makes the removing more efficient. The temperature has to be controlled carefully because if the temperature is too high then the enzymes active site gets permanently denatured and if the temperature is too low then the process will be too slow (these are the effects of variables on enzyme activity).


Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 01, 2009, 11:06:18 am
Part 1 - There are two types of micro-organisms which can be used to make enzymes - fungi or bacteria. The micro-organisms are then added a fermenter [which is a large, sterile container containing a stirrer, air pipes (to blow air into the mixture) and a pipe to add feedstock]. The temperature is maintained at about 26.c and at a pH of less then neutral (about 5-6). The enzymes produced are then of two types - extracellular (which are extracted from the foodstock by filtering) and intracellular (which are basically extracellular enzymes, crushed and washed with water); the enzymes are now in solution.

Part 2 - Enzymes help in removing stains from clothes because enzymes such as proteases break down blood stains (as blood contains the protein called haemoglobin) so then this makes it easier to remove stains. Furthermore, stains made by oils can also be removed because oils are lipids so they can be broken down by lipase enzymes into fatty acids and glycerol which makes the removing more efficient. The temperature has to be controlled carefully because if the temperature is too high then the enzymes active site gets permanently denatured and if the temperature is too low then the process will be too slow (these are the effects of variables on enzyme activity).



cool dude!!
she is asking about manufacture of insulin by bacteria...not enzymes...
so here u go

1)the gene responsible for the synthesis of insulin is selected from a human DNA
2)the gene is cut by the help of special enzymes(u do not need to know their names)
3)a bacteria cell is taken and the plasmid(round structure containing the genetic material of bacteria) is removed from it
4)the plasmid is cut open by the help of the same special enzyme and the gene for insulin is stuck to this plasmid by another set of enzymes
5)the enzyme for sticking is again used to close the plasmid
6)the plasmid is returned to the bacteria cell which now contains the gene to synthesize insulin
7)this bacteria is left to reproduce and a huge population of bacteria containing the insulin gene is produced
8)the bacteria cells produce the insulin which is extracted and used for human beings

I hope this makes it clear!!!
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 11:37:18 am
cool dude!!
she is asking about manufacture of insulin by bacteria...not enzymes...
so here u go

1)the gene responsible for the synthesis of insulin is selected from a human DNA
2)the gene is cut by the help of special enzymes(u do not need to know their names)
3)a bacteria cell is taken and the plasmid(round structure containing the genetic material of bacteria) is removed from it
4)the plasmid is cut open by the help of the same special enzyme and the gene for insulin is stuck to this plasmid by another set of enzymes
5)the enzyme for sticking is again used to close the plasmid
6)the plasmid is returned to the bacteria cell which now contains the gene to synthesize insulin
7)this bacteria is left to reproduce and a huge population of bacteria containing the insulin gene is produced
8)the bacteria cells produce the insulin which is extracted and used for human beings

I hope this makes it clear!!!


oh yeh sorry i answered the second part first cuz i knew that part better so i assumed that the first part mustve been related...:P....neway like it matters, u answered it...By the way stuck is kind of informal, better word would be incorporated....and just to impress the examiner nitya the enzyme is endonuclease..;)....(although like adi says its not required)

@adi-better brush up on ur vocab we've got p3 tomorrow
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 01, 2009, 11:41:46 am
dude vocab's not wat u really need tom....
wat i really need is my mind...
if its thee...i'll do wonders...
if its not ...the examiner will do wonders!!!
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 11:43:57 am
dude vocab's not wat u really need tom....
wat i really need is my mind...
if its thee...i'll do wonders...
if its not ...the examiner will do wonders!!!


lol, ur talkin as though u dnt hve ur mind half the time
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 01, 2009, 11:45:10 am
dude correct it!!!
i dont have my mind 3/4 th of the tym
can u plss reply to my pm..
i sent u 1 in the morning
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 11:47:06 am
dude correct it!!!
i dont have my mind 3/4 th of the tym
can u plss reply to my pm..
i sent u 1 in the morning


oh yeh sry bout that, the inbox notification is in such a small location i hardly notice it, w8 ill just reply
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 03:35:09 pm
hey thanks sooo much.. :) :) :) :) :) what r u all doing for bio??? just papers?
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 03:40:41 pm
o ya and best of luck for ur FLE paper... :) :)
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 04:08:05 pm
hey thanks sooo much.. :) :) :) :) :) what r u all doing for bio??? just papers?

Thanks for the luck nitya im gonna need it, yeh more or less im just gonna do june 09 once and read the guide got hist and maths that day too...:(:(:(:(
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 04:09:39 pm
poor u.. :P :P ...unfortunetly I dont hv d guide so sticking to past papers as usual...is d support chp imp?? u gonna do it??
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 04:11:01 pm
poor u.. :P :P ...unfortunetly I dont hv d guide so sticking to past papers as usual...is d support chp imp?? u gonna do it??


yep a bit of it and it wont kill u to read 3 pages either.....:P:P...just read the related part in the syll if ur so lazy..:P:P
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 04:14:01 pm
I already did that chp ... :P :P (proves m not LAZY) ;) :p ..but its hard to remember the bones and all.... so was just re-confirming nd By the way has nephrones cm in any past paper???
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 04:16:02 pm
I already did that chp ... :P :P (proves m not LAZY) ;) :p ..but its hard to remember the bones and all.... so was just re-confirming nd By the way has nephrones cm in any past paper???


yep june 08, and u dnt hve to remember all those bones!!!!!!!!! just the position of the tibia and fibula
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 04:19:35 pm
It's not as easy as that.. :P :P ... we need 2 do the movement of the forearm, the bones of the arm n shoulder, the joints, things in a joint and blah blah blah...there's a long list.. :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 04:26:18 pm
It's not as easy as that.. :P :P ... we need 2 do the movement of the forearm, the bones of the arm n shoulder, the joints, things in a joint and blah blah blah...there's a long list.. :P :P


yeh but i was talking about the bones as a seperate topic not about the whole of support and movement...:P:P:P
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 04:29:46 pm
But m talking about the whole chp.. :P :P Dont u hv 2 study.. u got an exam 2mrw right?? :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 04:32:40 pm
But m talking about the whole chp.. :P :P Dont u hv 2 study.. u got an exam 2mrw right?? :P :P

nope im readin the ers etc right so all my work is on the comp....nd dnt u hve an exam on wed..dnt u hve to study?..:P:P:P
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 04:37:00 pm
I have.. :P :P but its after 3 days n got 2 exams... :P :P urs is 2mrw and on wed that 2 3 papers..so total 4 paper in 3 days... proves that uve got MORE exams nd u need 2 study more.. :P :P...just kiddin ..no offense.. :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 01, 2009, 04:38:14 pm
hey thanks sooo much.. :) :) :) :) :) what r u all doing for bio??? just papers?
your welcome!!! :)
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 04:40:18 pm
I have.. :P :P but its after 3 days n got 2 exams... :P :P urs is 2mrw and on wed that 2 3 papers..so total 4 paper in 3 days... proves that uve got MORE exams nd u need 2 study more.. :P :P...just kiddin ..no offense.. :P :P

yeh i know but i dnt study as much as u do, do i bet ya i study as much for those 4 subs as u study for those 2 subs..:P:P:P
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 04:43:15 pm
well actually m not sure about that.. :P :P cuz m still muddled up in bio nd keep 4gettin easy things..always happens at d last moment...urghhh so annoyin..
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 04:45:31 pm
well actually m not sure about that.. :P :P cuz m still muddled up in bio nd keep 4gettin easy things..always happens at d last moment...urghhh so annoyin..

who stopped u from studying in the two week holiday we had...and now ur complainin ur forgettin things.....no offense..:P:P
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 04:47:15 pm
Irritatin person .. :P :P I mean 4gettin things out of nervousness ... :P :P nd i DO knw d answers but only if some1 prompts them at times lol ... ;)
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 04:48:56 pm
Irritatin person .. :P :P I mean 4gettin things out of nervousness ... :P :P nd i DO knw d answers but only if some1 prompts them at times lol ... ;)

so done wid bio and math, wat u doin for them?
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 04:57:01 pm
Done paper for both and read the chps again in Bio but only d 1's where I cant do the questions..
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 05:01:36 pm
Done paper for both and read the chps again in Bio but only d 1's where I cant do the questions..


ohh how many and wich papers hve u done for each sub?
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 05:06:52 pm
have done all but doing the question which I had trouble in again....nd also studyin from the Lets revision guide for Bio n solvin sums for maths from the Karren Morrison book
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 05:08:00 pm
have done all but doing the question which I had trouble in again....nd also studyin from the Lets revision guide for Bio n solvin sums for maths from the Karren Morrison book

okay
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 05:11:37 pm
what u doing for both d subs???
Title: Re: NEED HELP IN BIO!!!
Post by: cooldude on November 01, 2009, 05:18:42 pm
what u doing for both d subs???

math-ill do june 09 if i hve time
bio-ill read the guide and do june 09
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 01, 2009, 05:20:04 pm
those paper r really easy..wish we get similar ques... i just hate the plants questions and d chp..can never get d hang of it ...
Title: Re: NEED HELP IN BIO!!!
Post by: dlehddud on November 02, 2009, 03:51:08 am

oh yeh sorry i answered the second part first cuz i knew that part better so i assumed that the first part mustve been related...:P....neway like it matters, u answered it...By the way stuck is kind of informal, better word would be incorporated....and just to impress the examiner nitya the enzyme is endonuclease..;)....(although like adi says its not required)

@adi-better brush up on ur vocab we've got p3 tomorrow

and i think the enzyme used to cut the plasmid is ligase whilst the enzymes used to incorporate the insulin gene into the plasmid is endonuclease..  :P :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: nid404 on November 02, 2009, 04:00:32 am
and i think the enzyme used to cut the plasmid is ligase whilst the enzymes used to incorporate the insulin gene into the plasmid is endonuclease..  :P :P :P

yup that right
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 02, 2009, 04:26:15 am
Thanks guys really appreciate ur help :) :)
Title: Re: NEED HELP IN BIO!!!
Post by: leebux101 on November 02, 2009, 02:38:50 pm
yup that right
No ur wrong. It's the opposite, ligasr for joining and endonuclease for cutting. Read the book on tht part again.
Title: Re: NEED HELP IN BIO!!!
Post by: nid404 on November 02, 2009, 02:41:32 pm
No ur wrong. It's the opposite, ligasr for joining and endonuclease for cutting. Read the book on tht part again.

Restriction endonuclease is used to cut .....srry...I read his post wrong..

My apologies
Title: Re: NEED HELP IN BIO!!!
Post by: the_brainy_kid on November 02, 2009, 06:37:24 pm
Uhm, guys anybody thinks reproduction (as a chapter for godsake!) is REALLY important? Or can I do without it?
Title: Re: NEED HELP IN BIO!!!
Post by: sweetsh on November 02, 2009, 06:45:28 pm
No the brainy kid its important ofcourse, it's included in the syllabus and might appear
Title: Re: NEED HELP IN BIO!!!
Post by: the_brainy_kid on November 02, 2009, 06:49:40 pm
Sad. The chapter freaks me out. I'm more of the visual person (and a prude), so it becomes a bit difficult.  ;)
Thanks anyway sweetsh.
 ;D
Title: Re: NEED HELP IN BIO!!!
Post by: sweetsh on November 02, 2009, 06:50:11 pm
If you need any help in any past papers question ask
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 03, 2009, 04:28:18 am
Uhm, guys anybody thinks reproduction (as a chapter for godsake!) is REALLY important? Or can I do without it?
dude its one of the most important chapters in the syllabus....although all chapters are important as sweetsh rightly said...
often they do ask u to label stuff on the reproductive organs of the humans as well as plants....
what do u not understand???tell me specifically...perhaps i may help to explain it to u!!! :)
Title: Re: NEED HELP IN BIO!!!
Post by: the_brainy_kid on November 03, 2009, 11:03:18 am
what do u not understand???tell me specifically...perhaps i may help to explain it to u!!! :)
Haha. Thanks adi_toxic for the help. What's the main area you're revising from? The placenta stuff and the labelling?
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 03, 2009, 11:05:27 am
yup!!
placenta and all
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 03, 2009, 11:37:57 am
hey can some1 tell me about fermentation and all... i mean y is done ..hw is done ??? really confused in that...nd what type of ques cm in d past papers regarding that topic???
Title: Re: NEED HELP IN BIO!!!
Post by: dlehddud on November 04, 2009, 05:05:08 am
hey guys sat paper 3 2dae ><
it was hard as..
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 04, 2009, 12:46:42 pm
I know i sat 4 it 2...it was horrible...really unlike the others..
Title: Re: NEED HELP IN BIO!!!
Post by: the_brainy_kid on November 04, 2009, 01:08:51 pm
adi_toxic: you were wrong, if u get what m talking bout.  ;) See your replies in this post.
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 04, 2009, 01:37:32 pm
ya man!!!!
i regret not reading food additives well!!!
Title: Re: NEED HELP IN BIO!!!
Post by: bob on November 10, 2009, 06:39:07 am
yeah i know it was different from all the others..no reproduction, respiration n tons of other stuff that we thot was important never came! n damn those food additives..
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 10, 2009, 06:42:06 am
seriosuly dude...i hate cie ppl...i emphasized alot on this major topics but none came.... >:(
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 10, 2009, 07:04:14 am
same here... the 1 about nodules was also horrible.. nd the nitrogen cycle was way tougher this time...
Title: Re: NEED HELP IN BIO!!!
Post by: bob on November 10, 2009, 10:23:14 am
yeah that nitrogen cycle one that said explain how the nitrate ions are returned to the soil was 6 marks! i had no idea what to write for 6 marks so i jus made up tons o crap..n it even had a whole 'plot a graph' question..normally they're in ppr6..stupid ppl..had to change the paper this time..couldnt hav waited one more session  :(
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 10, 2009, 10:49:51 am
so truer.. I practically guessed the whole paper... and it was NOTHING like the past papers.. NOT EVEN 1 SINGLE QUES :'( :(
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:10:30 pm
heard p1 was too damn easy!!
some are expecting to get 41!!!
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 11, 2009, 01:13:00 pm
ya it was easy!! but 41??? huh?? d paper is 4 40 itself
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:13:30 pm
ya extra marks i mean!! :P
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 11, 2009, 01:14:21 pm
that cant happen in bio :P :P the examiners can cut marks simply if 1 reading is not within the range and thats risky :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 11, 2009, 01:14:28 pm
EXTRA MARKS FOR GOOD HANDWRITING
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:14:51 pm
MSQ mein from where does hanwritting come!!??? ???
Title: Re: NEED HELP IN BIO!!!
Post by: Ghost Of Highbury on November 11, 2009, 01:15:52 pm
good question.  ;)
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:16:23 pm
i guess he meant extra marks for good signature!! :P
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 11, 2009, 01:16:52 pm
heard pracs was too damn easy!!
some are expecting to get 41!!!
noooo...i guess som1 metioned prz and not mcq b4!!!!
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 11, 2009, 01:18:02 pm
lol ... :D
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:21:03 pm
adi you a true lol!!!
i talked abt paper 1 being easy!!

not ne other!!
and also i guess you have again stopped reading!! :D :D
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 11, 2009, 01:21:52 pm
oyee!!!
u mad??
abbey dekh to le what u said!!!
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 11, 2009, 01:22:17 pm
umm shrey u were actualyl tokin about the pracs.. :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:23:24 pm
heard p1 was too damn easy!!
some are expecting to get 41!!!
dude tu hi check kar le!!! :)
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 11, 2009, 01:24:47 pm
u EDITED it!! :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:25:22 pm
when did i!!
i just said and quoted wat i had written!!!
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 11, 2009, 01:26:48 pm
ya rite!! :P :P itna jhuta hai :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 11, 2009, 01:28:00 pm
abbey jaa teri BASS ki nahi hai!!!
fattu!!!
 ;D
 :D
 :D
 :D
 :D
loll.....jk..
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:29:03 pm
i know it was a joke!!
By the way how was p1???

some expecting 41!!!

now is this ok!??
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 11, 2009, 01:30:50 pm
ya much better :P :P paper1 mein 41 kaise aa sakte hai??? HANDWRITING BHI NAHI HOTA!! :P :P seedha seedha bol ki ppl r expectin full simple .. :P :P
Title: Re: NEED HELP IN BIO!!!
Post by: @d!_†oX!© on November 11, 2009, 01:31:49 pm
yaa....better now...line pe aa gaya.....lol

yeah...m expecting 43

mere preboards me 3 marks faltu ke kate the so compensation... ;)
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:32:30 pm
i meant it went so easy that some expecting abov 40!!
samjhi!!
it is an exasperation!
Title: Re: NEED HELP IN BIO!!!
Post by: nits94 on November 11, 2009, 01:33:19 pm
I know .. but really silly :P :P to aise to I shoul be expecting 45 cuz mere 4 marks compenstae hue and 1 mark 4 good signature ;)
Title: Re: NEED HELP IN BIO!!!
Post by: ~~~~shreyapril~~~~ on November 11, 2009, 01:33:51 pm
chalo i am leaving!
stop the EADA chats!!
go in EADA!!!