Carb Structure & Function

Question 1

All D-sugars have the hydroxide of their highest #ed chiral center on the ____, & all L-sugars have them on the _____.

Answer 1

Right & left (respectively)

Question 2

A special subtype of diastereomers where the difference is only @ 1 specific chiral center are known as ?

Answer 2

Epimers

Question 3

What is the difference between the alpha & beta anomers ?

Answer 3

alpha has OH group of C1 in trans position (axial & down), while beta has OH group of C1 in cis position (equatorial & up)

Question 4

Because aldoses can be oxidized, they are considered…?

Answer 4

Reducing agents

*Monosaccharide w/ hemiacetal ring = reducing sugar

Question 5

Oxidation of an aldose in ring form yields what ?

Answer 5

Lactone

Question 6

What 2 reagents are used to detect the presence of reducing sugars ?

Answer 6

1. Tollens’ reagent

2. Benedict’s reagent

Question 7

When an aldehyde group on an aldose is reduced to an alcohol this is called an ?

Answer 7

Alditol

Question 8

What is the main structural component in plants ?

Answer 8

Cellulose

*beta-D glucose molecules linked by beta 1, 4 glycosidic linkages

Question 9

What is the difference between alpha & beta amylase cleavage sites ?

Answer 9

a: cleaves randomly along chain to yield maltose & glucose
b: cleaves @ nonreducing end of polymer to yield maltose

Question 10

What enzyme cleaves glucose from glycogen @ the nonreducing end & phosphorylates it into glucose -1 -phosphate ?

Answer 10

Glycogen phosphorylase