We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
Click here to Donate Now (View Announcement)
I think that the chloride should be first reacted off by reacting the aluminium chloride with sodium hydroxide, which displaces chlorine from aluminium chloride resulting to aluminium hydroxide which can then be passed through electrolysis.Thanx!
Q(1)Suitable apparatus needed,A light source,a sound source(a speaker),a microphone, a light detector(ur eye, or a photoelectric detector,e.t.c), a stopwatch.a rule.q. the speed of sound waves in air may be determined by experiment usin a source that generates light n sound waves at the same time.
draw a labelled diagram of da arrangement of suitable apparatus for da experiment.
state the readings you would take
explain how you would calculate the speed of sound in air usin your readings.
q2. in an experiment to measureda distanc ebetweena thunderstorm an an individual(observer), why is light not taken into calculation?
pls any1 ans as soon as possible.
the syllabus mentions this point 2.1 which I would like to know about it :
Know that here are other classification
systems e.g. cladistics (based on RNA/
DNA sequencing data)
plz help exams are soon
Copper sulphate - BlueDoes anyone have a list of the colours for the different elements/compounds?
Like sometimes they will ask you for the colour for copper carbonate etc.
Is this in o.l biology? Because we only have the idea of resistance of bacteria to antibiotics , but not medicinal use of it, am i missing out something ?Describe the medicinal use of antibiotics for the treatment of bacterial infection. answer point-wise preferred and please include all we need to know regarding this question
THANK YOU
EXACTLY ! i was thinking the same thing but it was on the syllabus outline :/Is this in o.l biology? Because we only have the idea of resistance of bacteria to antibiotics , but not medicinal use of it, am i missing out something ?
for no 5. u r completely right... & the way u thought of the question is on right track.. but see , the thing is that the results are after 2 WEEKS as the pale speckled camouflaged so predators cant eat or hunt them down as they r hard to observe , unlike the black moths with can be easily caught... so after the 2 weeks when the moths are to be collected more speckled moths are collected since they camouflaged or in other words hid well ... while in no 4.a) u cant mention external features because by eye species cant be determined .. plus u should know that same species have similar origins of DNA so . if the DNA was tested u can simply differ between 2 species , HOPE THAT I COULD HELP .. even if a bitI have two Biology doubts ,both are in cambridge o.l igcse paper 3 exams:
1- In june 2007 , question no.5 it shows that the number of black moths caught 36, and the number of pale, speckled moths 82. Shouldn't the number of pale, speckled moths be less than that of the black moths. I mean the pale, speckled should be able to camouflage on the pale barks of the trees...
2- In June 2008 question 4 (a) why can't i say check if they have different external features ?
links for the two exams: 1-http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Biology (0610)/0610_s07_qp_3.pdf
2- http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Biology (0610)/0610_s08_qp_3.pdf
Thx in advance
I feel soo stupidfor no 5. u r completely right... & the way u thought of the question is on right track.. but see , the thing is that the results are after 2 WEEKS as the pale speckled camouflaged so predators cant eat or hunt them down as they r hard to observe , unlike the black moths with can be easily caught... so after the 2 weeks when the moths are to be collected more speckled moths are collected since they camouflaged or in other words hid well ... while in no 4.a) u cant mention external features because by eye species cant be determined .. plus u should know that same species have similar origins of DNA so . if the DNA was tested u can simply differ between 2 species , HOPE THAT I COULD HELP .. even if a bit
Well anyway i don't think you need to worry about it .Althought it is isn't in my biology notes, but it simply has the same idea of manufacture of SCP and of insulin, just the use of fermenter and providing suitable temperature and ventilation, food,pH ...etc then collect the filtrate.EXACTLY ! i was thinking the same thing but it was on the syllabus outline :/
http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Biology (0610)/0610_y12_sy.pdf
(pg. 33)
yeah me either :/ alright , but can it be assumed that it's also talking about what the antibiotic does to the bacteria as well as the process of extreacting it?Well anyway i don't think you need to worry about it .Althought it is isn't in my biology notes, but it simply has the same idea of manufacture of SCP and of insulin, just the use of fermenter and providing suitable temperature and ventilation, food,pH ...etc then collect the filtrate.
hmm looking back at your answer i am not so sure :\ I know the answer for what was mentioned in the syllabus is wat i said, but i think your question mean how does antibiotics fight bacterial infection. My guess is: non-mutant bacteria are killed by anti-biotics which can penetrate the bacteria's capsule and kill the bacteria which was causing the infection. But i am so unsure abt this , so its best to check the mark scheme and tell me what did you find good luckyeah me either :/ alright , but can it be assumed that it's also talking about what the antibiotic does to the bacteria as well as the process of extreacting it?
andddd thank you so much !
hmm looking back at your answer i am not so sure :\ I know the answer for what was mentioned in the syllabus is wat i said, but i think your question mean how does antibiotics fight bacterial infection. My guess is: non-mutant bacteria are killed by anti-biotics which can penetrate the bacteria's capsule and kill the bacteria which was causing the infection. But i am so unsure abt this , so its best to check the mark scheme and tell me what did you find good luck
For almost 10 years, the site XtremePapers has been trying very hard to serve its users.
However, we are now struggling to cover its operational costs due to unforeseen circumstances. If we helped you in any way, kindly contribute and be the part of this effort. No act of kindness, no matter how small, is ever wasted.
Click here to Donate Now