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Biology; Chemistry; Physics: Post your doubts here!

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these are pretty easy and u can find answers in Atps as well for the first one u need lagging material on one beaker and compare with another without lagging and write the experiment like u do in ATP s !

for the second one u can do plenty of stuff,i remember this one put pollen grains in water and u will see pollen grains moving in a random pattern showing that water molecules moving randomly colliding with pollen grains :D

this is just brief i can explain further if u want ?

Whats is ATPs?
 
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this is because perfume contains Alcohol which is Volatile Liquid ...it gains the Energy from the body , and Vaporizes and take the heat from the body
reducing the temperature of the body and producing cooling affect
thnkx alot!
 
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Assalam-o-Allaikum and Hi everyone ,
hope u all are doin great !

Well as the topic says help for chemistry :D biology :D and Physics :D is available here that means that u can ask any mind blowing question or ask any question regarding a particular topic or ask abt any questions from Past paper or any of your text books. (y) (y)

I made this topic so that people dont make many posts asking abt bio,physics or chemistry individually but they can post their reply here where it can be answered with ease and the members wont have to go searching for topics to help! :D !

So what are u waiting for now write ur questions here !
THANKS and Bye or Allah Hafiz ! :wink: :good:

how to download all biology pastpapers together?????
 
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okay so-- i i just finished grade 8 and next year i will start grade 9 IG ,, but the problem is - i don't know what or how to study and i don't understand this whole A level O level thing . so if some one helped me that would be really great
 
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okay so-- i i just finished grade 8 and next year i will start grade 9 IG ,, but the problem is - i don't know what or how to study and i don't understand this whole A level O level thing . so if some one helped me that would be really great
You will be doing O level first, O level means Ordinary Level! and A level means Advanced Level.
If you are science student then you will be studying Biology, Chemistry and Physics ! In Biology you will study about the Environment, Human anatomy [ like how digestion works or circulatory system works ] Plant Anatomy [ how water is absorbed by plants or how plants transport water around and also make their own food ] In chemistry you will be studying about chemicals, Acids and salts which will differ from our everyday terms! And In chemistry you will need to know quite a lot of experiments, color changes, and predict color of compounds! Write chemical Equations and balance them. For Physics you will study motion, forces, and how each other works together! for example a motion is produced when you apply a force and when work is done! [ you will know this when you study ] My biggest advice is get a really strong Foundation now, and then O level will be easy for you! Reading is not important but, understanding why, how, when, what is important, try to guess what type of questions will come ;)! and make your own questions! Being an examiner yourself will improve you!
 
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Anyone know in which coaching centres Sir Naushad(physics) is teaching(karachi) these days!! It would be be helpful if you can tell coaching centres in or near GULSHAN-E-IQBAL or GULISTAN-E-JAUHAR!! PLEASE REPLY AS SOON AS POSSIBLE!!! THANKS!!
 
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okay so-- i i just finished grade 8 and next year i will start grade 9 IG ,, but the problem is - i don't know what or how to study and i don't understand this whole A level O level thing . so if some one helped me that would be really great
Me too got out of grade 8, and now onwards I am going to grade 9
 
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Me too got out of grade 8, and now onwards I am going to grade 9
Stick to the forum and also get help in any doubt you have! this will greatly improve your grades.....If you do well at grade 9 and 8 you will be doing very good in 10, all your work depends on the work you do now! so use your time efficiently and well, try to score 100/100 in your current exams :)! Remember there are people who get 100/100 in O level exam also in School exams from whole syllabus [ everything that you will study ] and you will be only tested with few topics from the syllabus so there is no reason for why you can't get full marks (Y)! Aim for 100 and work for it :D! You will succeed in the mercy of Allah :)!
 
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shudnt your question be why it is less common in these areas rather than more common if its more common than ive got the answer to ur present question Why is it that Malaria is common in many parts of the world where the sickle cell allele is present in the population? this is becuz if u look at how these people have blood cells which are half moon shaped then it makes these people more prone to death by Malaria as the virus can destroy their cells more easily and the ones that are normal if killed can cause that guy to get severe breathlessness and probably death,i dont really get the concept of resistance from Malaria if u have sickle cell anaemia read the article below if u too are confused :D
http://www.sicklecell.md/faq.asp
Can you please help me out with the following questions?

Q1. Explain the role of Penicillium in the production of penicillin.
Q2. Before Penicillium or the medium is put into the fermenter, it is cleaned with hot steam.
(a) Suggest why this is necessary.
(b) Suggest why the air supply to the fermenter comes into the base of it rather than the top
(c) Explain why it is important that carbon dioxide is allowed to escape from the fermenter.
Q3. Suggest 2 similarities and 1 difference between the conditions required in a fermenter used for making enzymes for biological washing powders and one used for making penicillin.
 
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I need help in Biology.
should we learn asexual reproduction in bacteria, fungi, natural vegetative propagation in flowering plants, artificial vegetative propagation for 2013 may june exam cie syllabus (5090)
 
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should we learn asexual reproduction in bacteri, fungi, natural vegetaive propagation and artificial vegetative propagation for may june 2013 exam for cie syllabus
 
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Can you please help me out with the following questions?

Q1. Explain the role of Penicillium in the production of penicillin.
Q2. Before Penicillium or the medium is put into the fermenter, it is cleaned with hot steam.
(a) Suggest why this is necessary.
(b) Suggest why the air supply to the fermenter comes into the base of it rather than the top
(c) Explain why it is important that carbon dioxide is allowed to escape from the fermenter.
Q3. Suggest 2 similarities and 1 difference between the conditions required in a fermenter used for making enzymes for biological washing powders and one used for making penicillin.

A1. this question is kind of stupid Penicillium is the organism which produces penicillin,penicillin is actually the excretory by product of Penicillium ( try not confusing the terms :D ) so its actually the main thing required which grows and multiplies in the culture solution and then u get the penicillin :D

A2a this is a necessity becuz like any other place with lots of water and food stuff in this water bacteria grows and fungus also grows so by using hot steam we end up sterilizing the ferementer and then immediately after wards the solution is poured and the lid closed to allow for no bacteria to enter the ferementer and disturb the penicillin growth :p

A2b it comes from the base because as we know that air will be less dense than the solution we will be using,so entering it from bottom is better so air actually goes into the solution and not outside straight away :D Also we have the impeller down there so it helps mixing the air with the solution better

A2c Penicillium like all living beings needs O2 to live and Making it breathe in CO2 will cause it to respire anaerobically and produce very little penicillin or even nothing so like us it needs to live with O2 and by living it carries out the process by which we get Penicillin :D

A3c this question i have no idea abt if u are giving O level biology then was the syllabus changed or something becuz in 2012 they didnt have this :p but ill study and let u know :D
 
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A1. this question is kind of stupid Penicillium is the organism which produces penicillin,penicillin is actually the excretory by product of Penicillium ( try not confusing the terms :D ) so its actually the main thing required which grows and multiplies in the culture solution and then u get the penicillin :D

A2a this is a necessity becuz like any other place with lots of water and food stuff in this water bacteria grows and fungus also grows so by using hot steam we end up sterilizing the ferementer and then immediately after wards the solution is poured and the lid closed to allow for no bacteria to enter the ferementer and disturb the penicillin growth :p

A2b it comes from the base because as we know that air will be less dense than the solution we will be using,so entering it from bottom is better so air actually goes into the solution and not outside straight away :D Also we have the impeller down there so it helps mixing the air with the solution better

A2c Penicillium like all living beings needs O2 to live and Making it breathe in CO2 will cause it to respire anaerobically and produce very little penicillin or even nothing so like us it needs to live with O2 and by living it carries out the process by which we get Penicillin :D

A3c this question i have no idea abt if u are giving O level biology then was the syllabus changed or something becuz in 2012 they didnt have this :p but ill study and let u know :D
Thanks a lot..!!!! :D
And please let me know the last answer when u have found it. In fact, i remember noting this question down from a book in my school library so i guess its not out of syllabus.
In the meanwhile, can u pls explain question 5c(ii) of the IG paper I am uploading. I have my exams in two days so please help me out... Thanks again :)
 

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A1. this question is kind of stupid Penicillium is the organism which produces penicillin,penicillin is actually the excretory by product of Penicillium ( try not confusing the terms :D ) so its actually the main thing required which grows and multiplies in the culture solution and then u get the penicillin :D

A2a this is a necessity becuz like any other place with lots of water and food stuff in this water bacteria grows and fungus also grows so by using hot steam we end up sterilizing the ferementer and then immediately after wards the solution is poured and the lid closed to allow for no bacteria to enter the ferementer and disturb the penicillin growth :p

A2b it comes from the base because as we know that air will be less dense than the solution we will be using,so entering it from bottom is better so air actually goes into the solution and not outside straight away :D Also we have the impeller down there so it helps mixing the air with the solution better

A2c Penicillium like all living beings needs O2 to live and Making it breathe in CO2 will cause it to respire anaerobically and produce very little penicillin or even nothing so like us it needs to live with O2 and by living it carries out the process by which we get Penicillin :D

A3c this question i have no idea abt if u are giving O level biology then was the syllabus changed or something becuz in 2012 they didnt have this :p but ill study and let u know :D
What do you use to study? you really good at science subjects (Y)!
 
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