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Flashcards in Carbohydrates Deck (318)
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1

What is the general formula for COH's?

Cx(H2O)x

2

What is the molecular formula of most common monosaccharides?

C6H12O6

3

What bond links disaccharides?

glycosidic

4

Maltose is a common....

enzymatic hydrolysis product of starch

5

What do we commonly use sucrose as on a daily basis?

Table sugar

6

Lactose is the major sugar in what?

Cow's milk

7

How many monosaccharides are oligosaccharides made up of? Linked together by what type of bonds?

3-10, glycosidic bonds

8

What is an example of a trisaccharide? What are its 3 monomers?

Raffinose- galactose, glucose, fructose

9

Maltose =

glucose + glucose

10

Sucrose =

Glucose + fructose

11

Lactose =

glucose + galactose

12

What is an example of a tetrasaccharide? What are its 4 monomers?

Stachyose - glucose + fructose + galactose + galactose

13

How many monomers do polysaccharides have?

>10

14

What are 5 examples of polysaccharides found in nature?

1. starch
2. cellulose
3. glycogen
4. pectin
5. xanthan gum

15

What are 4 common roles of carbohydrates in living systems?

1. An energy source in seeds - starch for germination
2. Structural component - cellulose and hemicellulose
3. A ready supply of energy - mono- and disaccharides
4. short-term energy supply for muscles - glycogen

16

What are 3 functions of mono- and disaccharides in foods?

1. Sweetening agents
2. Coloring agents (caramel color)
3. Production of flavors (caramelization/Maillard reaction)

17

What are 7 functions of polysaccharides in foods?

1. Tickening agents
2. water-holding/binding agents
3. Anticaking agents
4. Gelling agents
5. Emulsion stabilizers
6. For producing edible films
7. To encapsulate flavors

18

In addition to having multiple alcohol functional groups, they have either a _______ or an _______ functional group (in their linear form).

ketone
aldehyde

19

How is the carbon chain of monosaccharides numbered?

from the aldehyde (C-1) or the ketone (C-2) functional group down

20

What is the smallest monosaccharide?

Glyceraldehyde (C3)

21

For glyceraldehyldes, the D or L isomerism refers to the ________ carbon.

Asymmetric C

22

For other sugars, D or L isomerism refers ONLY to the _____________ and not any of the other asymmetric carbons that may be in the chain.

1. n-1 carbon (2nd from the bottom)

23

Optical isomers involving asymmetric carbons other than the carbon at the n-1 position are considered ________ or _______

different sugars

epimers

24

All C6 monosaccharides are epimers of ______. Examples?

Glucose

Ex: D-mannose is a C-2 epimer of D-glucose

25

Monosaccharides can be classified on the basis of _______ and _______.

Carbon number

Functional group

26

What type of compound is a ketohexose? Aldohexose? Aldopentose?

C6 ketone
C6 aldehyde
C5 aldehyde

27

Cyclization is due to the formation of internal ______ and _______

hemiacetals
hemiketals

28

Are the reactions involving the cyclization of monosaccharides intermolecular or intramolecular?

Intramolecular - the aldehyde or ketone group and the alcohol group are in the same molecule

29

What compounds make up hemiacetals?

Alcohol + aldehyde

30

What compounds make up hemiketals?

Alcohol + ketone