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    "The availability of nitrogen containing compounds in the soil is often the limiting factor for plant growth. Explain two ways on which a shortage of nitrogen-containing compounds could limit plant growth."

    I havent really got many ideas. Is this all to do with making DNA strands , aminoacids and proteins? But what else? I don't really know what else you can make from nitrogen for plants...:o:

    It's a synoptic question from the Environment old spec Aqa B. It's 4 marks.

    Please help anyone! It's bugging me lol. Will rep!
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    Nitrogen is mainly taken up as Nitrate. It is taken up both passively and actively. When it is converted in to AAs such as Glutamate, the AAs are used for protein synthesis. So Nitrogen is an essential part of proteins, enzymes etc and it is in every plant cell. It is also part of cholorophyll, so is needed for photosynthesis. I think that's the 2 things (the proteins etc and chlorophyll).
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    Ahhh thanks!

    I hve another question btw:

    "Suggest an explanation for the % of energy lost in faeces for the herbivore being larger than that for the carnivore."

    is that due to herbivores consuming food that is low in energy value? So a lot is excreted as it's waste e.g. Grass. And carnivores eating very high energy food? Plus carnivores are more active so have to catch prey so lots of energy wasted in respiration?!

    Thanks. :o:
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    (Original post by Alisa25)
    Ahhh thanks!

    I hve another question btw:

    "Suggest an explanation for the % of energy lost in faeces for the herbivore being larger than that for the carnivore."

    is that due to herbivores consuming food that is low in energy value? So a lot is excreted as it's waste e.g. Grass. And carnivores eating very high energy food? Plus carnivores are more active so have to catch prey so lots of energy wasted in respiration?!

    Thanks. :o:

    Herbivores by definition consume plant material which is undigested such as cellulose in cell walls and lignin in xylem tubes...because they don't possess the enzymes to digest such compounds..
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    (Original post by Alisa25)
    Ahhh thanks!

    I hve another question btw:

    "Suggest an explanation for the % of energy lost in faeces for the herbivore being larger than that for the carnivore."

    is that due to herbivores consuming food that is low in energy value? So a lot is excreted as it's waste e.g. Grass. And carnivores eating very high energy food? Plus carnivores are more active so have to catch prey so lots of energy wasted in respiration?!

    Thanks. :o:
    What it says above ^^^^. They consume plants, so a larger proportion of their diet is undigestable.
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    Also, some herbivores then eat their faeces to get that energy (I think rabbits but not entirely sure)...
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    Hiii

    Are you doing the BYB5 exam?
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    (Original post by Alisa25)
    Ahhh thanks!

    I hve another question btw:

    "Suggest an explanation for the % of energy lost in faeces for the herbivore being larger than that for the carnivore."

    is that due to herbivores consuming food that is low in energy value? So a lot is excreted as it's waste e.g. Grass. And carnivores eating very high energy food? Plus carnivores are more active so have to catch prey so lots of energy wasted in respiration?!

    Thanks. :o:
    I remember this from the past paper.

    Herbivores eat lots of plants
    plants have cellulose
    Most of it's not digested
    undigested food has energy so this is lost.

    What you wrote is correct.
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    (Original post by crazyness)
    Hiii

    Are you doing the BYB5 exam?
    Yeas.

    Retaking it.
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    (Original post by Alisa25)
    Yeas.

    Retaking it.
    me 2. Good luck. Just memorise the mark scheme.
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    (Original post by crazyness)
    me 2. Good luck. Just memorise the mark scheme.
    High five!!!

    I'm dreading it tbh. I've got a B in bio overall but I'm trying for an A! I doubt I'll get it though... I need Very high A's to get That overall A..

    Good luckto you too!
 
 
 
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