Protein structure, saccharides and fats

[dudeman2491]

Hi,
Just need to clear up any misunderstanding about protein structure. Do all proteins have at least three levels of structure? If a protein has a quaternary structure, does it mean it also has primary, secondary and tertiary structures?

I was wondering what separates a polysaccharide from a disaccharide? What number is the minimum amount of monosaccharides that make a polysaccharide.

My last question is in regards to saturated and unsaturated fats. If i have two saturated fatty acids and one unsaturated fatty acid to combine with glycerol to make a fat. Is the resulting fat unsaturated because it can still incorporate more hydrogen? Is it true that if there is a double bonded carbon in the fat, it is considered unsaturated?

Thanks

 

[epenguin]

Hi,
Just need to clear up any misunderstanding about protein structure. Do all proteins have at Hi,
Just need to clear up any misunderstanding about protein structure. Do all proteins have at least three levels of structure? If a protein has a quaternary structure, does it mean it also has primary, secondary and tertiary structures?

Yes. Quaternary structure just means the way more than one polypeptide chain is associated together.

I was wondering what separates a polysaccharides from a disaccharide?

If you were talking in general, e.g. about a mixture of all lengths you could call them all polysaccharides if they are more than two or even more than one Usually polysaccharide suggests something quite large though. With just a moderate number, "a few" they tend to be called oligosaccharides. Wiki gives 3-10. Same thing for oligo/poly peptides. oligo/poly nucleotides.

My last question is in regards to saturated and unsaturated fats. If i have two saturated fatty acids and one unsaturated fatty acid to combine with glycerol to make a fat. Is the resulting fat unsaturated because it can still incorporate more hydrogen? Is it true that if there is a double bonded carbon in the fat, it is considered unsaturated?

Thanks

Yes.

And if it isn't it ought to!

Do not worry too much about the precise limits of these terms which are not quite rigid. Just read the biochemistry and see how they are used.