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Course: High school biology > Unit 1
Lesson 2: Important molecules for biology- Elements and atoms
- Introduction to carbohydrates
- Introduction to proteins and amino acids
- Introduction to lipids
- Introduction to nucleic acids and nucleotides
- Introduction to vitamins and minerals
- Biological macromolecules review
- Biological macromolecules
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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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- 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 :))(59 votes) - Since glucose is the building block for glycogen, is starch and glycogen the same thing?(12 votes)
- 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)
- 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)- 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)
- 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)- 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)
- 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)
- Glucose is just one type of sugars.
You are talking about table sugar - that is sucrose.
Succrose is disaccharide produced of two types - glucose and fructose.
Basically they proces snatural sugars, remove fibers etc,
This link illustrates it on the example of orange, ornage juice and orange soda. And the dagers of loophole FDA made with processing sugars.
http://sitn.hms.harvard.edu/flash/2015/natural-and-added-sugars-two-sides-of-the-same-coin/(8 votes)
- Can someone summarize this please because I don't know what most of these words mean.(4 votes)
- 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)
- What does it mean when you say we're made out of Carbon atoms ?(3 votes)
- 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)
- 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)- poly means many, and for saccharide, i think you just spelled it wrong, sit it comes up as a carbohydrate for me(4 votes)
- What are monomers and polymers?(3 votes)
- What are the organic chemical groups that compose carbohydrates? How are carbohydrates classified according to the presence of those groups?(3 votes)
- 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.