All Questions
23
questions
6
votes
2
answers
161
views
What does ‘D’ in GADP (glyceraldehyde 3-phosphate) stand for?
Wikipedia says glyceraldehyde-3-phosphate can be abbreviated as G3P, GA3P, GADP, GAP, TP, GALP or PGAL, and many resources seem to use GADP as its abbreviation.
I have no idea where ‘D’ came from. ...
- 129
0
votes
0
answers
27
views
Why can't the fructose monomer in sucrose be α-fructose?
In all academic sources, sucrose is identified as α−glucose (1-->2) β−fructose. However, I cannot find any explanation anywhere as to why the fructose monomer has to be in the β configuration. ...
- 11
-1
votes
2
answers
2k
views
Are Starch, Amylose and, Amylopectin reducing sugars?
Amylose and Amylopectin;
As per the information I've learnt, Amylose is considered a reducing sugar but Amylopectin is not because Amylose has a free "reducing end" which Amylopectin lacks, ...
0
votes
1
answer
410
views
Does changes in pH affects cyclic form of glucose in water solution?
Glucose in water solution is mainly in cyclic form. Both base and acid can catalize formation of hemiacetal, but in distinct mechanisms. I found information that monosacharides eg. glucose exist ...
0
votes
0
answers
2k
views
Haworth structures of sucrose and lactose
The haworth structures of lactose and sucrose is
My question is regarding the glyosidic linkage, in lactose it is represented as a zig zag and in sucrose it is a "V". What does that mean. ...
user95393
2
votes
0
answers
212
views
Do enzymes that digest ᴅ-glucose react with ʟ-glucose?
ᴅ-Glucose is common in nature and ʟ-glucose is synthesized in the lab.
I know that humans can't use ʟ-glucose in their aerobic pathways because it doesn't match the active site of the enzyme, but why ...
- 29
7
votes
2
answers
3k
views
Oxidation of hydroxyl groups of glucose
In all oxidation reactions of glucose, it seems that the aldehyde group alone gets oxidised and none of the hydroxyl groups. In one reaction with nitric acid, the aldehyde group and the terminal ...
- 103
5
votes
2
answers
3k
views
How does existence of alpha and beta form of glucose prove that it exists as a cyclic structure
My book says that
Glucose is found to exist in two different crystalline forms which are
named as $\alpha$ and $\beta$.
Next it says that
This behaviour could not be explained by the open ...
- 305
6
votes
4
answers
4k
views
Why is fermentation of cellulose to produce biofuel and nutrients so difficult?
The formula for glucose is $\ce{C6H12O6}$ and that of cellulose is very similar $\ce{C6H10O5}$. Glucose can be readily fermented by yeast and other micro-organisms to produce carbon dioxide and ...
- 357
0
votes
1
answer
705
views
Glycoside Formation Reaction
Whenever we add $\ce{H+}$/ Ethanol to glucose in its hemiacetal form, why doesn't pinacone/pinacolone rearrangement take place in place of nucleophillic substitution. The product would lead to ...
- 1,132
9
votes
3
answers
27k
views
How do you recognize a carbohydrate molecule?
I am studying carbohydrates in organic chemistry and I am confused a bit on what they are and how you recognize whether a molecule is a carbohydrate or not. For example, will a carbohydrate always ...
- 1,096
-4
votes
2
answers
17k
views
In Glucose, how will you prove the presence of the following? [closed]
One carbonyl group
5 hydroxyl groups
One primary alcholic group
- 99
-2
votes
1
answer
746
views
Why isn't sucrose a reducing sugar but maltose is? [duplicate]
I read one of the answers for a similar question, According to that it is due to the hemiacetale group converting into a carbonyl group. I don't get why the same thing can't be applied to sucrose ...
3
votes
1
answer
187
views
Gel filtration separation of cellulose, starch, oxytocin and palmitic acid
I am studying biochemistry and I have been asked by my teacher to find a procedure for separating cellulose, starch, the peptide oxytocin (9 a.a) and palmitic acid ($\ce{C16}$) using gel filtration ...
- 140
9
votes
1
answer
3k
views
Why do polysaccharides consisting of alpha-glucose have helical structures?
Why do the polysaccharides consisting of alpha-glucose such as starch and glycogen have helical structure, while the one such as cellulose consisting of beta glucose don't display such structures?
The ...
- 93