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    Hey keen biologists since the exam is very soon, it would be good to test each other on exam questions.

    I'll start off by posting a question and whoever answers it has to ask a question themselves

    Alright here we gooo
    'Explain why burning wood is described as 'carbon neutral' unlike the burning of a fossil fuel. (2)
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    (Original post by NilabKebab)
    Hey keen biologists since the exam is very soon, it would be good to test each other on exam questions.

    I'll start off by posting a question and whoever answers it has to ask a question themselves

    Alright here we gooo
    'Explain why burning wood is described as 'carbon neutral' unlike the burning of a fossil fuel. (2)

    Hello,

    I am also doing this test.

    I'm going to have a crack at the question, here it goes:

    Wood fuel contains stored energy from the sun through photosynthesis. So chemical energy in wood can therefore be passed on as heat energy to us. Wood fuel is a renewable energy source because by growing tress the carbon dioxide levels will be kept the same in the carbon cycle as long as new trees are planted.

    But as for Fossil fuels is non renewable, and carbon dioxide trapped within the fossil fuels are released into the atmosphere adding to the cycle.

    By the way, the subject of the forum says 2012.

    ?
    ?I think the question I have is slightly nasty, but here it goes:

    Describe and explain how the theory of evolution is supported by DNA evidence. (4)
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    Ahh my mistake, still haven't got used to the new year :rolleyes:

    Good answer, you receive one mark for stating amount of CO2 produced is equal to amount absorbed and and second mark for stating fossil fuels release carbon back into atmosphere. 2 marks awarded

    Alright here is my answer to your question:

    The theory of evolution is that different species can be traced back to a common ancestor and that many complex organisms grew from being a simple organisms.
    DNA evidence includes DNA profiling, DNA sequencing, DNA molecular clocks and DNA hybridisation.
    In DNA hybridisation, two different DNAs are heated and H bonds break. They can be mixed to form a hybrid DNA. Not all bases pair up, the more the bases stick together, it indicates that species are closely related. This supports theory of evolution because it shows that species are related thus could derive from a common ancestor.
    In DNA sequencing, DNA bases are known and the bases of two different species are compared to see how many match. The fewer differences, the more closely related they are.
    In DNA profiling, a sample of DNA is taken and amplified using PCR. Then it goes through electrophoresis which separates DNA fragments depending on where the restriction enzymes cut them. Different bands are formed and two different species DNA profile is compared to observe how many bands actually match. The more bands match, the more closely related they are. These pieces of evidence all show if species have derived from a common ancestor- if they have DNA bases will be similar thus will show similarities.
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    Moved to the biology exams sub-forum, best of luck in your exam everyone
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    (Original post by Eloades11)
    Moved to the biology exams sub-forum, best of luck in your exam everyone
    Thank you, I am quite new to TSR as you have noticed
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    (Original post by NilabKebab)
    Ahh my mistake, still haven't got used to the new year :rolleyes:

    Good answer, you receive one mark for stating amount of CO2 produced is equal to amount absorbed and and second mark for stating fossil fuels release carbon back into atmosphere. 2 marks awarded

    Alright here is my answer to your question:

    The theory of evolution is that different species can be traced back to a common ancestor and that many complex organisms grew from being a simple organisms.
    DNA evidence includes DNA profiling, DNA sequencing, DNA molecular clocks and DNA hybridisation.
    In DNA hybridisation, two different DNAs are heated and H bonds break. They can be mixed to form a hybrid DNA. Not all bases pair up, the more the bases stick together, it indicates that species are closely related. This supports theory of evolution because it shows that species are related thus could derive from a common ancestor.
    In DNA sequencing, DNA bases are known and the bases of two different species are compared to see how many match. The fewer differences, the more closely related they are.
    In DNA profiling, a sample of DNA is taken and amplified using PCR. Then it goes through electrophoresis which separates DNA fragments depending on where the restriction enzymes cut them. Different bands are formed and two different species DNA profile is compared to observe how many bands actually match. The more bands match, the more closely related they are. These pieces of evidence all show if species have derived from a common ancestor- if they have DNA bases will be similar thus will show similarities.
    Hey

    That's an awesome answer going to include it in my notes

    My question

    Describe the role of microorganisms in the decomposition of plant material
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    Okay I got a question, not really in exam paper style but on our spec it says describe ...blah blah.. @measurement of a biotic factors e.g. climate topography" how the hell would you measure that, I don't even know what it is??

    Any help would be appreciated.
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    (Original post by mohamedsuleman94)
    Okay I got a question, not really in exam paper style but on our spec it says describe ...blah blah.. @measurement of a biotic factors e.g. climate topography" how the hell would you measure that, I don't even know what it is??

    Any help would be appreciated.
    From my notes:

    Climate Topography

    Ø Relief (how the height of the land changes across a surface) can be measured by taking height readings using a GPS device at different point across the surface. You can also use maps with contour lines (lines that join points that are the same height).

    Ø Slope angle (how steep a slope is) is measured suing a clinometer. A simple clinometer is just a piece of string with a weight on the end attached to the centre of a protractor. You point the flat edge of the protractor up the hill, and read the slop angle off the protractor.

    Ø Aspect (the direction a slope is facing) is measured using a compass.
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    (Original post by NilabKebab)
    Ahh my mistake, still haven't got used to the new year :rolleyes:

    Good answer, you receive one mark for stating amount of CO2 produced is equal to amount absorbed and and second mark for stating fossil fuels release carbon back into atmosphere. 2 marks awarded

    Alright here is my answer to your question:

    The theory of evolution is that different species can be traced back to a common ancestor and that many complex organisms grew from being a simple organisms.
    DNA evidence includes DNA profiling, DNA sequencing, DNA molecular clocks and DNA hybridisation.
    In DNA hybridisation, two different DNAs are heated and H bonds break. They can be mixed to form a hybrid DNA. Not all bases pair up, the more the bases stick together, it indicates that species are closely related. This supports theory of evolution because it shows that species are related thus could derive from a common ancestor.
    In DNA sequencing, DNA bases are known and the bases of two different species are compared to see how many match. The fewer differences, the more closely related they are.
    In DNA profiling, a sample of DNA is taken and amplified using PCR. Then it goes through electrophoresis which separates DNA fragments depending on where the restriction enzymes cut them. Different bands are formed and two different species DNA profile is compared to observe how many bands actually match. The more bands match, the more closely related they are. These pieces of evidence all show if species have derived from a common ancestor- if they have DNA bases will be similar thus will show similarities.
    Great Answer. Full Marks.
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    (Original post by C94)
    From my notes:

    Climate Topography

    Ø Relief (how the height of the land changes across a surface) can be measured by taking height readings using a GPS device at different point across the surface. You can also use maps with contour lines (lines that join points that are the same height).

    Ø Slope angle (how steep a slope is) is measured suing a clinometer. A simple clinometer is just a piece of string with a weight on the end attached to the centre of a protractor. You point the flat edge of the protractor up the hill, and read the slop angle off the protractor.

    Ø Aspect (the direction a slope is facing) is measured using a compass.
    Thanks
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    Thank you, I was taken back by the question for a second before my brain started functioning properly lol

    Here is my answer to his question:
    Describe the role of microorganisms in the decomposition of plant material

    Microorganisms break down plant material into its components. For example enzymes in decomposers such as cellulase breaks down cellulose (a key plant material) into its monosaccharides- beta glucose. Microorganisms decompose material in metabolic reactions, carried out by enzymes- which are specific and break down one product in plant material. The process of decomposition releases gases like CO2 and CH4 into the atmosphere.

    I am not sure if that really answers the question...was slightly off point. What do you guys think?
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    (Original post by NilabKebab)
    Thank you, I was taken back by the question for a second before my brain started functioning properly lol

    Here is my answer to his question:
    Describe the role of microorganisms in the decomposition of plant material

    Microorganisms break down plant material into its components. For example enzymes in decomposers such as cellulase breaks down cellulose (a key plant material) into its monosaccharides- beta glucose. Microorganisms decompose material in metabolic reactions, carried out by enzymes- which are specific and break down one product in plant material. The process of decomposition releases gases like CO2 and CH4 into the atmosphere.

    I am not sure if that really answers the question...was slightly off point. What do you guys think?
    Yeah really good answer, the important point is that it contributes to the carbon cycle, by releasing the gases, just like you said.

    My answer I have learnt for this particular question is.

    Microorganisms such as Bacteria and fungi decompose organic matter. They are an important part of the carbon cycle. When plants and animals die, microorganisms on and in them secrete enzymes and decompose the dead organic material into smaller molecules that they can respire. When the microorganisms respire these small molecules, methane and CO2 are released, this recycles carbon back into the atmosphere.
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    Ok, I think a good tip is to come up with key words associated with the answer, it will help steer towards the right direction.

    Eg in your answer key words would be bacteria/fungi, respiration, contribution to carbon cycle, CO2/CH4, enzymes.

    Here is another question: suggest why planting more trees will not reduce CO2 levels in the long term? (3)
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    (Original post by NilabKebab)
    Thank you, I was taken back by the question for a second before my brain started functioning properly lol

    Here is my answer to his question:
    Describe the role of microorganisms in the decomposition of plant material

    Microorganisms break down plant material into its components. For example enzymes in decomposers such as cellulase breaks down cellulose (a key plant material) into its monosaccharides- beta glucose. Microorganisms decompose material in metabolic reactions, carried out by enzymes- which are specific and break down one product in plant material. The process of decomposition releases gases like CO2 and CH4 into the atmosphere.

    I am not sure if that really answers the question...was slightly off point. What do you guys think?

    id like to refer back to your answer on dna hybridisation. the key thing to mention was the difference in temperatures at which the hybrid dna would denture. the hybrid dna denatures at lower temperatures than the pure dna due to not being stable.

    and yeah your answer is correct but u shud refer to how that co2 is released i.e due to respiration as well and that it gets reabsorbed by plants for photosynthesis. methane is produced in anaerobic conditions and used as a fossil fuel.
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    (Original post by Hdizzle)
    id like to refer back to your answer on dna hybridisation. the key thing to mention was the difference in temperatures at which the hybrid dna would denture. the hybrid dna denatures at lower temperatures than the pure dna due to not being stable.

    and yeah your answer is correct but u shud refer to how that co2 is released i.e due to respiration as well and that it gets reabsorbed by plants for photosynthesis. methane is produced in anaerobic conditions and used as a fossil fuel.
    Hmm yes that is the key point about DNA hybridisation. Ok thank you for the improvement tips, I will include it in my revision notes.
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    (Original post by NilabKebab)
    Ok, I think a good tip is to come up with key words associated with the answer, it will help steer towards the right direction.

    Eg in your answer key words would be bacteria/fungi, respiration, contribution to carbon cycle, CO2/CH4, enzymes.

    Here is another question: suggest why planting more trees will not reduce CO2 levels in the long term? (3)

    Come on let's revive the thread

    Ive been trying to form an answer worth 3 marks for your question. But can't seem to think of one

    Will attempt

    1)initially co2 will be absorbed for photosynthesis
    2)as trees grow the difference between the co2 absorbed and released reduces and eventually there will no longer be a decrease in co2 levels
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    Yah good answer

    You could also add
    -there is a limit to how much trees can be grown (land space) and money to plant and maintain trees
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    There is this amazing website with loads of exam questions

    Here is the weblink
    http://clc2.uniservity.com/GroupWork...vascript=False
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    (Original post by NilabKebab)
    There is this amazing website with loads of exam questions

    Here is the weblink
    http://clc2.uniservity.com/GroupWork...vascript=False
    thanks a mill


    would rate you but have to rate someone else first
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    (Original post by Hdizzle)
    thanks a mill


    would rate you but have to rate someone else first
    Caj :P

    lol why the neg rate?

    New question:
    Explain how new alleles might appear in the gene pool of a species. (2)
 
 
 
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