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    Hey so Im just revising my AS biology and was wondering if someone could give me a hand as i am confused about glucose:

    So,
    Alpha Glucose can bind to Alpha glucose in a 1,4- glycocidic bond (?) in a condensation reaction (creating what). I also think that Alpha and Beta Glucose can join in 1,6- glycocidic bonds (creating what?). But i was wondering, as Beta Glucose is just like alpha but with the hydoxyl group swapped around, can this also create 1,4- Glycocidic bonds? and if so, does this create the same thing??

    So in short:
    What does 2 alpha Glucose bind to make?
    What does alpha and beta glucose bind to make?
    Can 2 Beta glucose bind together? if so, what kind of bonds and what does it make?

    And, if you have any other information about this topic that i need to know, please include that too,
    THANKS
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    alpha glucose does bind to another alpha glucose to for a 1,4 alpha glycosidic bond. (say alpha too in the bond because you are more likely to get the mark).

    Condensation is creating this 1,4 alpha glycosidic bond. Its the reaction that the two alpha glucose molecules go through.

    The 1,6 glycosidic bond is also alpha so the full name is 1,6 alpha glycosidic bond because two alpha molecules create it in a condensation reaction. This makes either glycogen or amylopectin (a branch of glycogen).

    1,4 glycosidic bond are made with only alpha molecules or with beta molecules. it cannot be made with an alpha and beta molecule. 1,4 alpha glycosidic bonds will create starch or amylose and 1,4 beta glycosidic bonds will create cellulose.

    2 alpha glucose molecules bind to make a dissacharide.

    No such reaction exists with an alpha molecule and beta molecule
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    What exam board do you follow?
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    Hi, need to help you with a small correction and addition to HajraMomoniat's input.

    1. I am not sure what he/she means by "amylopectin is a "branch" of glycogen" {a polysachharide cannot have a branch that is a completely separate polysaccharide!) - glycogen is a polysaccharide (highly branched) that is the form in which ANIMALS store carbohydrate (mainly in liver and muscle); amylopectin has nothing to do with glycogen. Amylose and amylopectin are the substances that make up starch, which is the storage form of carbohydrate IN PLANTS.

    Amylose is made from alpha glucose, amylopectin from beta glucose, glycogen from alpha glucose and cellulose from beta glucose. (ANOTHER IMPORTANT DIFFERENCE BETWEEN amylopectin AND glycogen).

    The confusion in the above post might be the fact that both glycogen and amylopectin are branched polysaccharides, which is a completely different thing.

    It is also crucial to point out that:-

    1. Two molecules of glucose combine to form maltose, three to form maltotiose.

    2. A condensation reaction involves the shedding of a molecule of water.

    3. A series of 1,4 - glycosidic bonds produces a straight chain, whereas addition of 1,6 - glycosidic bonds results in branching (to understand why, AND to make it much easier to remember, look at the structural formula of two glucose molecules side by side, and look at where carbon 1, 4 and 6 lie. In a standard diagram , C1 is on the right, C4 on the left, and C6 at the top (above the O). So if you think about it, 1, 4 linkages (between carbon 1 of the gkucose on the left and carbon 4 of glucose on the right, ditto, ditto, ditto........................... ........... will produce a "horizontal" straight chain. As soon as any glucose in this STRAIGHT chain creates a bond by its carbon 6 (on top) with the C1 of a new glucose molecule, you will obviously get the start of a "vertical branch" - therefore, 1,6 - bonds lead to branching as in amylopectin and in glycogen.

    4. Amylose is made of 200-5000 alpha glucose units; amylopectin of 5000-100,000 beta glucose units.

    5. Glycogen is a smaller molecule than amylopectin, but is more highly branched.

    Regards, Mukesh (Specialist Biology Tutor)
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    (Original post by macpatelgh)
    Hi, need to help you with a small correction and addition to HajraMomoniat's input.

    1. I am not sure what he/she means by "amylopectin is a "branch" of glycogen" {a polysachharide cannot have a branch that is a completely separate polysaccharide!) - glycogen is a polysaccharide (highly branched) that is the form in which ANIMALS store carbohydrate (mainly in liver and muscle); amylopectin has nothing to do with glycogen. Amylose and amylopectin are the substances that make up starch, which is the storage form of carbohydrate IN PLANTS.

    Amylose is made from alpha glucose, amylopectin from beta glucose, glycogen from alpha glucose and cellulose from beta glucose. (ANOTHER IMPORTANT DIFFERENCE BETWEEN amylopectin AND glycogen).

    The confusion in the above post might be the fact that both glycogen and amylopectin are branched polysaccharides, which is a completely different thing.

    It is also crucial to point out that:-

    1. Two molecules of glucose combine to form maltose, three to form maltotiose.

    2. A condensation reaction involves the shedding of a molecule of water.

    3. A series of 1,4 - glycosidic bonds produces a straight chain, whereas addition of 1,6 - glycosidic bonds results in branching (to understand why, AND to make it much easier to remember, look at the structural formula of two glucose molecules side by side, and look at where carbon 1, 4 and 6 lie. In a standard diagram , C1 is on the right, C4 on the left, and C6 at the top (above the O). So if you think about it, 1, 4 linkages (between carbon 1 of the gkucose on the left and carbon 4 of glucose on the right, ditto, ditto, ditto........................... ........... will produce a "horizontal" straight chain. As soon as any glucose in this STRAIGHT chain creates a bond by its carbon 6 (on top) with the C1 of a new glucose molecule, you will obviously get the start of a "vertical branch" - therefore, 1,6 - bonds lead to branching as in amylopectin and in glycogen.

    4. Amylose is made of 200-5000 alpha glucose units; amylopectin of 5000-100,000 beta glucose units.

    5. Glycogen is a smaller molecule than amylopectin, but is more highly branched.

    Regards, Mukesh (Specialist Biology Tutor)
    For your information I am a female and I have used the Aqa biology cgp books as well as http://www.thealevelbiologist.co.uk/carbohydrates

    I made a mistake yes when I was typing but amylopectin is a type of starch where it is made from alpha glucose.
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    (Original post by macpatelgh)
    Hi, need to help you with a small correction and addition to HajraMomoniat's input.

    1. I am not sure what he/she means by "amylopectin is a "branch" of glycogen" {a polysachharide cannot have a branch that is a completely separate polysaccharide!) - glycogen is a polysaccharide (highly branched) that is the form in which ANIMALS store carbohydrate (mainly in liver and muscle); amylopectin has nothing to do with glycogen. Amylose and amylopectin are the substances that make up starch, which is the storage form of carbohydrate IN PLANTS.

    Amylose is made from alpha glucose, amylopectin from beta glucose, glycogen from alpha glucose and cellulose from beta glucose. (ANOTHER IMPORTANT DIFFERENCE BETWEEN amylopectin AND glycogen).

    The confusion in the above post might be the fact that both glycogen and amylopectin are branched polysaccharides, which is a completely different thing.

    It is also crucial to point out that:-

    1. Two molecules of glucose combine to form maltose, three to form maltotiose.

    2. A condensation reaction involves the shedding of a molecule of water.

    3. A series of 1,4 - glycosidic bonds produces a straight chain, whereas addition of 1,6 - glycosidic bonds results in branching (to understand why, AND to make it much easier to remember, look at the structural formula of two glucose molecules side by side, and look at where carbon 1, 4 and 6 lie. In a standard diagram , C1 is on the right, C4 on the left, and C6 at the top (above the O). So if you think about it, 1, 4 linkages (between carbon 1 of the gkucose on the left and carbon 4 of glucose on the right, ditto, ditto, ditto........................... ........... will produce a "horizontal" straight chain. As soon as any glucose in this STRAIGHT chain creates a bond by its carbon 6 (on top) with the C1 of a new glucose molecule, you will obviously get the start of a "vertical branch" - therefore, 1,6 - bonds lead to branching as in amylopectin and in glycogen.

    4. Amylose is made of 200-5000 alpha glucose units; amylopectin of 5000-100,000 beta glucose units.

    5. Glycogen is a smaller molecule than amylopectin, but is more highly branched.

    Regards, Mukesh (Specialist Biology Tutor)
    mate amylopectin is made up of a-glucose not beta. with branching
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    (Original post by tk1611)
    Hey so Im just revising my AS biology and was wondering if someone could give me a hand as i am confused about glucose:

    So,
    Alpha Glucose can bind to Alpha glucose in a 1,4- glycocidic bond (?) in a condensation reaction (creating what). I also think that Alpha and Beta Glucose can join in 1,6- glycocidic bonds (creating what?). But i was wondering, as Beta Glucose is just like alpha but with the hydoxyl group swapped around, can this also create 1,4- Glycocidic bonds? and if so, does this create the same thing??

    So in short:
    What does 2 alpha Glucose bind to make?
    What does alpha and beta glucose bind to make?
    Can 2 Beta glucose bind together? if so, what kind of bonds and what does it make?

    And, if you have any other information about this topic that i need to know, please include that too,
    THANKS
    Why is everyone making this so complicated lol?
    1. Maltose
    2. That doesn't happen
    3. Yes. They can form a polymer called cellulose. 1-4 Beta glycosidic bonds. Straight chained.
 
 
 
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