Monosaccharide vs. disaccharide vs. polysaccharides

I am taking bio101 and have a question about monosaccharide, disaccharides, and polysaccharides. Let me try and explain and let me know if I'm right.

monosaccharide are just one molecule of a simple suger ie, glucose, fructose.

disaccarides have just one molecule of 2 simple sugars ie they aren't multiple glucose molecules only 1 plus 1 other simple sugar molecule.

polysaccarides are a chain of 1 type of simple molecule, ie there could be 10,000 glucose molecules combined.

Reply 1

Bionic Bunny

Monosaccharides are the simplest form of carbohydrates. There is dextrose (glucose), fructose, galactose (milk sugars), and ribose.

Reply 2

BENCHMARKMAN

OP

1

Bionic Bunny

Monosaccharides are the simplest form of carbohydrates. There is dextrose (glucose), fructose, galactose (milk sugars), and ribose.

Thanks but that didn't really answer my question. Was what I said above true? I want to know about how many total molecules are in each. Thanks

Reply 3

vickyrkenya

2

BENCHMARKMAN

I am taking bio101 and have a question about monosaccharide, disaccharides, and polysaccharides. Let me try and explain and let me know if I'm right.

monosaccharide are just one molecule of a simple suger ie, glucose, fructose.

disaccarides have just one molecule of 2 simple sugars ie they aren't multiple glucose molecules only 1 plus 1 other simple sugar molecule.

polysaccarides are a chain of 1 type of simple molecule, ie there could be 10,000 glucose molecules combined.

Oh heck...ive been out of university too long...this SHOULD be correct information...

Your first statement about monosaccharides is correct. Disaccharides are composed of two monosaccharides as you correctly stated. They can be two of the same type e.g. 2 glucose monomers combine to give a maltose molecule. They can also be two different monosaccharides e.g. galactose and glucose combine to give lactose. The formation of this disaccharide from two monosaccharides is a condensation reaction and a glycosidic bond is formed between the two monomers.

Polysaccharides can be formed from many different monosaccharides (heteropolysaccharides) or many of the same type (homopolysaccharides).

Hope this helps you.

Reply 4

ChemistBoy

16

What you have put is essentially correct. There are also oligosaccharides which are short chains of sugars (3 - 20+ ish) which are important for cell recognition, etc. Of course the overlap of oligo and poly saccharides is fuzzy at best!

Reply 5

BENCHMARKMAN

OP

1

Thanks for the replies. We have only talked about the saccarides that I mentioned above. Maybe later on in the course the others will be mentioned. I have the first exam tomorrow, I feel pretty good about the material.