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Flashcards in 2Rings And Variants Deck (43):
0

Aldehyde + alcohol

Hemiacetal

1

Ketone + alcohol

Hemiketal

2

Which two groups react to form a hemiacetal on the glucose molecule?

The alcohol on carbon #5 and the aldehyde of carbon#1 react since they are closest to rah other and form the ring.

3

Alpha Hemiactetal is due to:

The OH group pointing down on carbon #1

4

Beta Hemiacetal is due to:

The OH group is pointing up

5

What form is 99% of glucose in?

Ring structure alpha or beta


Mostly the beta conformation

6

Which of the following is an anomeric pair?

(Differs only in configuration at hemiacetal or hemiketal carbon)

Alpha-D-glucose and Beta-D- glucose

7

Glucose is the oxidizing sugar that is reduced into:

D-Glucitol

8

Glucose turns into Glucitol by:

Reducing an aldehyde into an alcohol on c#1

9

Glucose turns into gluconate by:

Oxidizing the aldehyde group to Carboxylic acid...this would be oxidized sugar

10

Sugars that can undergo oxidation are called:

Reducing sugars


Diabetes test: copper turned brick red with urine...copper was reduced because the sugar became oxidized

11

Sugars with aldehyde groups are...

Reducing sugars

12

Oxidizing sugar

Oxidizes other substances and gains electrons so the oxidation state will decrease.


The oxidize sugar will gain oxygen and release hydrogen.

13

Reducing sugar

The aldehyde functional group allows the sugar to act as a reducing agent. You aldehyde can be oxidized via a redox reaction in which another compound is reduced. Thus, a reducing sugars one that reduces certain chemicals.

The reducing sugar will gain hydrogen and lose oxygen

Glucose turns into gluconate

14

Fructose is a _____ sugar

Fructose can be a reducing sugar because it can isomerize to glucose or mannose, this happens very slowly at room or body temperature but it is very rapid when heated in the test tube.

Can rearrange to be a reducing sugar.

15

D-glucose is called a reducing sugar because it undergoes an oxidation – reduction reaction at the anomeric carbon. What are the products of this reaction is:

D-glauconate

16

D- Ribose structure

H O
\ //
H- C - OH
l
H- C -OH
l
H- C-OH
l
CH2OH

17

Deoxy-D- Ribose

*deoxy

Removed OH on C#2


H O
\ //
C
l
H- C- H
l
H- C- OH
l
H- C- OH
l
CH2OH

18

Oxidized sugars

Beta-D- Glucoronate
Carboxylic acid on carbon #6

D-Gluconate
Oxidize carbon #1 and Carboxylic acid where aldehyde used to be and can form ring

D-Glucono-S- lactone
Ring formed from Carboxylic acid on carbon #1

19

Glucuronates are very useful in helping to excrete:

Less than water soluble molecules

They increase water solubility of target molecules to facilitate excretion from the body.

Ex: Bilirubin- a break down product from heme and can conjugate to Glucoronate to increase water solubility

20

Direct Bilirubin

It is water-soluble in a conjugated form that is attached to two glucuronates to the Bilirubin molecule

21

Indirect Bilirubin

It is the non-conjugated form that is usually found bound to albumin in the blood

22

Oxidize sugars are also known as

Acidic sugars

23

Modified acidic sugar:

NANA

N-Acetylneuramibic acid

24

Amino sugars:

Has nitrogens instead of oxygens on the sugar rings.

Ex: Beta-D- Galactosamine
Has NH2 in position #2

and Beta-D- Mannosamine
Has mannose in N #2

25

Common sugar abbreviations

Fructose. Fru
Galactose. Gal
Glucose Glc
mannose man
ribose. Rib


Glucuronic acid. GlcA
Galactosamine. GalN
Glucosamine. GlcN
N-acetyl galactose amine. GalNAc
N-acetyl glucosamine GlcNAc

26

Which of the following monosaccharides is not a carboxylic acid?

Glucose

27

Which of the following is anomeric pair?

Same structure but OH group flipped to opposite sides

Alpha-D- glucose and Beta-D-glucose

28

Which of the following sugars contain a Ketone?

Fructose

29

Which seven of the following sugars are monosaccharides?

Galactose
Ribose
Glyceraldehyde
Glucuronate
Mannose
Glucose
Fructose

30

Which of the following sugars contains only glucose?

Maltose

31

Which of the following sugars would test negative to the reducing sugar test?

Sucrose

32

What is the configuration of D – glyceraldehyde?

R

33

Which of the following is a five carbon sugar?

Ribose

34

Which of the following is an epimer of glucose?

Mannose

35

Fructose contains which of the following functional groups?

Keytone and alcohol

36

If a urine sample of a diabetic patient has copper (II) nitrate added to it, is heated and as a result a brick red precipitate forms, what most likely happened?

Glucose is oxidized

37

The reduced form of glucose is named?

Sorbitol

38

When glucose forms a ring, what happened?

One of the alcohol groups reacted with the aldehyde

39

Which of the following is contains glucose (Alpha 1–4) bond?

Maltose
Amylose

40

The enzyme lactase, found in our intestine, breaks which type of bond?

Gal( beta1-4)

41

Which of the following bond is found in glycogen?

Glu(alpha1-6)
Glu(alpha 1-4)

42

What is another biochemical name for repeating disaccharide?

Glycan