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Introduction to carbohydrates

A carbohydrate is a type of molecule that contains carbon, hydrogen, and oxygen. Carbohydrates can be simple sugars (monosaccharides) like glucose, or they can be made up of multiple sugar units (polysaccharides) like glycogen. They are important in biology as a source of energy and as structural components in plants.

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  • sneak peak green style avatar for user Sumit
    For anyone who needs a summary:
    Carbohydrates are a type of molecule that have carbon and have one oxygen for every two hydrogen, same as water. Carbohydrates can be simple sugars, monosaccharides like glucose (monomer), or complex sugars make of many glucose units, polysaccharides like glycogen (polymer). They are important as sources of energy and make structural components in plants.

    If there are anythings I could add lmk :))
    (62 votes)
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  • female robot grace style avatar for user Ting Yi Chew
    Since glucose is the building block for glycogen, is starch and glycogen the same thing?
    (12 votes)
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    • orange juice squid orange style avatar for user Lily
      They are very similar to one another, however they aren't exactly the same thing. Both are not just linear chains of glucose molecules, but they are branched. Glycogen is more extensively branched than starch and it's also more compact. Also, starch occurs in plants and glycogen in animals.
      (30 votes)
  • leaf blue style avatar for user Sarah
    I've seen some new elements replacing the old ones:
    1. Uut = Ununtrium - Nh = Nihonium
    2. Uuq = Ununquadium - Fl = Flerovium
    3. Uup = Ununpentium - Mc = Moscovium
    4. Uuh = Ununhexium - Lv = Liverium
    5. Uus = Ununseptium - Ts = Tennessine
    6. Uuo = Ununoctium - Og = Oganesson
    What are these unknown elements and how did they come about?
    (15 votes)
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    • aqualine ultimate style avatar for user Russell
      These are all lab-created elements that are not known to appear in nature. Most of these have the "Unun" prefix name when they are first discovered and do not have an official name yet, but are eventually given actual names, often crediting the finder in some way.
      (11 votes)
  • leaf blue style avatar for user Prakrati
    Wait so what is the difference between a polymer and a polysaccharide?
    And monomer and monosaccharide?
    Or do they both mean the same thing?
    (9 votes)
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    • aqualine ultimate style avatar for user You
      Hello awesomeblue4. The answer to your third question is no they may sound and seem to have the same word but they are completely different meanings and properties as well. I have listed them below.

      What is the difference between a polymer and a polysaccharide?

      A polymer is a substance composed of molecules with large molecular mass composed of repeating structural units, or monomers, connected by covalent chemical bonds. While a polysaccharide is a polymer made up of many monosaccharides joined together by glycosidic linkages. They are therefore very large, often branched, molecules. They tend to be amorphous and insoluble in water

      What is the difference between monomer and monosaccharide?

      A monomer, simply, is the general term for anything that is the building block of something larger(polymers). But monosaccharides are an example of a monomer.

      Hope this helps
      Alphy :)
      (15 votes)
  • piceratops ultimate style avatar for user Leonardo Padro
    Is sugar made completely out of glucose or is there other stuff in there and if sugar is made completely out of glucose why do they have to process the sugar cane plant to make sugar?
    (9 votes)
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  • stelly blue style avatar for user eliana.hernandez.lee
    Can someone summarize this please because I don't know what most of these words mean.
    (4 votes)
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    • mr pink red style avatar for user Forever Learner
      basically its talking about how carbs are made up. they can be monosacharides-one piece things. or they can be polysacharides-made up of many pieces. and he went over that carbs are basically just carbons and water in different arrangements. glucose is a carb he went over, and he said that one is used to store energy. hope that helps
      (13 votes)
  • aqualine ultimate style avatar for user Jasmine Roush
    What does it mean when you say we're made out of Carbon atoms ?
    (3 votes)
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    • stelly yellow style avatar for user ⭐BEST20042007⭐
      Hi Jasmine! When Sal said we are made up of Carbon atoms, he means that most of our body mass is mostly carbon. For example, carbon atoms are in our hair, skin, and all of our cells are made up of large amounts of carbon. For a clearer picture, carbon makes up 18.5% of our body mass. That's alot if you think about it.

      Furthermore, if you want to know the reason why carbon takes up 18.5% of our body mass, I'll explain. Carbon atoms are unique because they have the ability to form bonds with up to 4 other atoms at the same time (simultaneously). As a result, this lets carbon atoms form long chains of molecules to serve as a base for life. Some examples include DNA and other proteins.

      I hope this helped!
      (5 votes)
  • winston baby style avatar for user Mason Smith
    I have a couple questions,
    1. what does the prefix "poly" mean?

    2. I looked up the word Saccharide, and it came up as Vietnamese,
    why is that?
    (3 votes)
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  • male robot hal style avatar for user Bart
    What are monomers and polymers?
    (3 votes)
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  • blobby green style avatar for user lavasha.howard25
    What are the organic chemical groups that compose carbohydrates? How are carbohydrates classified according to the presence of those groups?
    (3 votes)
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    • blobby green style avatar for user SkyStalker007
      All carbohydrates consist of carbon, hydrogen, and oxygen atoms and are polyhydroxy aldehydes or ketones or are compounds that can be broken down to form such compounds. Examples of carbohydrates include starch, fiber, the sweet-tasting compounds called sugars, and structural materials such as cellulose.

      How are carbohydrates classified? Carbohydrates are divided into four types: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Monosaccharides consist of a simple sugar; that is, they have the chemical formula C6H12O6. Disaccharides are two simple sugars.
      (3 votes)

Video transcript

- [Instructor] What we're going to do in this video is give ourselves a quick introduction to carbohydrates, and you might already be familiar with the notion. If you look at some packaged food, there's usually a nutritional label and will say carbohydrates. It will tell you a certain number of grams per serving. And not all carbohydrates are edible, but many of the things that we eat or many carbohydrates are edible and many of the foods we eat have some carbohydrate component to it. But what is it actually? Well, we can look at the word and we see carbo, so maybe it has something to do with carbons. And it says hydrates, so maybe it has something to do with water. And if you said that, you'd be pretty close because carbohydrates do involve carbons. In fact, this is a very typical carbohydrate, a very simple one right over here. This is a glucose molecule. And in gray, you see that it has six carbons. And the hydrate part refers to, that carbohydrates typically have oxygen to hydrogens in the same ratio as you would expect in water. So, for every one oxygen, two hydrogens, and you see that right over here, where in glucose, you have one, two, three, four, five, six oxygens and you have 12 hydrogens, and so that's where this word comes from. Now, another word that is often used interchangeably with carbohydrates is the term saccharide. Saccharide, and saccharide comes from Greek for sweet, and that makes sense because if you were to taste glucose, it would taste sweet to you. Now, what's interesting about something like glucose is glucose can be a standalone molecule, a very simple sugar in this case or you can build up larger molecules with really glucose as a building block. So for example, right over here, we have a part of a glycogen molecule. And as you can see, it's just a repeating sequence of glucose molecules. And so, something like this, we would call glucose a monosaccharide. It's one simple sugar right over here. Monosaccharide. And we would call this glycogen a polysaccharide. Polysaccharide. Or another way to think about it is glucose is the building block for the glycogen. Another term you might see is monomer and polymer. Those are the general terms or if I'm building a large molecule out of a chain of smaller ones, the building blocks, we consider to be monomers, and then the thing that we build out of those monomers could be our polymer. And as we'll see, this monomer polymer phenomenon is not limited to carbohydrates or saccharides. We're gonna see that same relationship, for example, between amino acids and proteins. Now, what role do carbohydrates play inside of biological systems? Well, saccharides or carbohydrates are often associated with the source energy. Glucose can be converted very quickly to energy in biological cells. Glycogen is also a store of energy in your liver and your muscles. And once again, it can be broken down into the glucose molecules, which once again, is a very readily available source of energy. Now, in plants especially, some of these polysaccharides could also play a structural role if we're talking about things like cellulose, which is another polysaccharide. So, there's also a structural role. Now, I will leave you there. We have focused only on one type of monosaccharide in glucose, and only on one type of polysaccharide in glycogen. As we will see, glucose does show up a lot but there are many other types of monosaccharides and there are many other types of polysaccharides. And polysaccharides in particular are part of a broader group of molecules known as macromolecules. And as you can imagine, from the macro prefix, it's referring to large molecules, oftentimes that have thousands of atoms in them. But don't get the wrong idea. They're very large at an atomic level but each of these circles are still atoms, so you would still need a very, very, very, very powerful microscope to even to take a look at even some of the largest macromolecules, including polysaccharides.