Biochemistry Lecture 24- Carbs

Front 1

The electron carriers in cells, NAD+/NADH, FAD/FADH2, and NADP/NADPH must

Back 1

The electron carriers in cells, NAD+/NADH, FAD/FADH2, and NADP/NADPH must cycle between oxidized and reduced forms.

Front 2

NAD+/NADH, FAD/FADH2, and NADP/NADPH are present in limiting amounts in cells, so______

Back 2

NAD+/NADH, FAD/FADH2, and NADP/NADPH must cycle between oxidized and reduced forms. They are present in limiting amounts in cells, so having adequate quantities of them for metabolic oxidation/reductions requires that they be balanced

Front 3

To convert NADH to NAD+ or FADH2 to FAD requires

Back 3

To convert NADH to NAD+ or FADH2 to FAD requires "dumping" of electrons and protons into the electron transport system.

Front 4

To convert NADH to NAD+ or FADH2 to FAD requires "dumping" of electrons and protons into the electron transport system. Failure to do that may _______________

Back 4

To convert NADH to NAD+ or FADH2 to FAD requires "dumping" of electrons and protons into the electron transport system. Failure to do that may require cells to go through fermentation.

Front 5

Glucose and fructose differ only that

Back 5

Glucose and fructose differ only that glucose is an aldehyde, where as fructose is a ketone. Both have six carbons

Front 6

The letters 'ose' at the end of a name designate

Back 6

The letters 'ose' at the end of a name designate a sugar.

Front 7

aldose

Back 7

aldose is a sugar, like glucose, that is an aldehyde.

Front 8

ketose

Back 8

ketose is a sugar like fructose that is a ketone.

Front 9

A hexose has ___ carbons

Back 9

A hexose has six carbons

Front 10

pentose has ____ carbons

Back 10

pentose has five carbons

Front 11

a tetrose has ________ carbons

Back 11

a tetrose has four carbons

Front 12

a triose has _____ carbons

Back 12

a triose has three carbons

Front 13

The L form of a sugar (like L-glucose) differs from the D form of a sugar of the same name (like D-glucose) in that

Back 13

The L form of a sugar (like L-glucose) differs from the D form of a sugar of the same name (like D-glucose) in that the two are mirror images of each other.

Front 14

diastereomers

Back 14

Sugar molecules that have the same number of carbons, and have different stereoisomeric configurations but that are NOT mirror images of each other are called diastereomers.

Front 15

Sugars can form a ring structure due to

Back 15

Sugars can form a ring structure due to the fact that carbons 1 and 5 (or 2 and 5) are located in close promity to each other and the alcohol on carbon 5 can react with the aldehyde on carbon one or the ketone on carbon two to form a hemiacetal or hemiketal respectively.

Front 16

Haworth projection

Back 16

Sugars can form a ring structure due to the fact that carbons 1 and 5 (or 2 and 5) are located in close promity to each other and the alcohol on carbon 5 can react with the aldehyde on carbon one or the ketone on carbon two to form a hemiacetal or hemiketal respectively. The resulting ring structure is called a Haworth projection.

Front 17

Fischer projection.

Back 17

Sugars can form a ring structure due to the fact that carbons 1 and 5 (or 2 and 5) are located in close promity to each other and the alcohol on carbon 5 can react with the aldehyde on carbon one or the ketone on carbon two to form a hemiacetal or hemiketal respectively. The linear form, as written, is called a Fischer projection.

Front 18

pyranoses

Back 18

sugars, like glucose, that form six membered rings are called pyranoses

Front 19

furanoses

Back 19

sugars, like fructose and ribose, that form five membered rings are called furanoses.

Front 20

Formation of a ring creates

Back 20

Formation of a ring creates a new asymmtric carbon (called the anomeric carbon) on the carbon where the aldehyde or ketone originally was (carbon 1 or 2).

Front 21

Formation of a ring creates a new asymmtric carbon (called the anomeric carbon) on the carbon where the aldehyde or ketone originally was (carbon 1 or 2). The hydroxyl on this carbon can exist in a Haworth projection pointing ____________

Back 21

Formation of a ring creates a new asymmtric carbon (called the anomeric carbon) on the carbon where the aldehyde or ketone originally was (carbon 1 or 2). The hydroxyl on this carbon can exist in a Haworth projection pointing upwards (beta) or downwards (alpha).

Front 22

Linear forms of these sugars DO NOT have _______________, since the ____________ is what creates the asymmetry.

Back 22

Linear forms of these sugars DO NOT have anomeric carbons, since the cyclization is what creates the asymmetry.

Front 23

Aldoses, like glucose, are readily

Back 23

Aldoses, like glucose, are readily oxidized.

Front 24

Ketoses are NOT nearly as readily oxidized as ___________.

Back 24

Ketoses are NOT nearly as readily oxidized as aldoses.

Front 25

sorbitol

Back 25

Reduction of the aldehye or ketone structure of a sugar can lead to compounds like sorbitol that are sometimes called sugar alcohols.

Front 26

Replacement of the hydrogen on the hydroxyl of an anomeric carbon by any other atom creates a

Back 26

Replacement of the hydrogen on the hydroxyl of an anomeric carbon by any other atom creates a glycoside.

Front 27

Many carbohydrates containing multiple sugar units have __________ bonds.

Back 27

Many carbohydrates containing multiple sugar units have glycosidic bonds.

Front 28

Replacement of the hydrogen on the hydroxyl of an anomeric carbon by any other atom creates a glycoside. The bond is referred to as a _________ bond.

Back 28

Replacement of the hydrogen on the hydroxyl of an anomeric carbon by any other atom creates a glycoside. The bond is referred to as a glycosidic bond.

Front 29

Sucrose (glucose + fructose) has a ______________ joining the two sugars, as does lactose (glucose + galactose).

Back 29

Sucrose (glucose + fructose) has a glycosidic bond joining the two sugars, as does lactose (glucose + galactose).

Front 30

disaccharides

Back 30

Carbohydrates with two sugars are known as disaccharides.

Front 31

Sugars that are not glycosides can

Back 31

Sugars that are not glycosides can change readily from alpha to beta, but glycosides are locked in the configuration they were in when the hydrogen was replaced from the hydroxyl group of the anomeric carbon.

Front 32

polysaccharides

Back 32

Polymers of sugars create polysaccharides.

Front 33

Amylose is a

Back 33

Amylose is a polysaccharide of plants that consists of glucose units linked solely in alpha-1,4 linkages.

Front 34

Glycogen is

Back 34

Glycogen is a storage polysaccharride of animals that contains glucose units linked in alpha1,4 linkages and every ten residues or so, there is a 1,6 branch to a new chain of glucose.

Front 35

Glycogen is therefore __________.

Back 35

Glycogen is therefore very branched.

Front 36

Amylopectin is

Back 36

Amylopectin is a polysaccharide of plants that also is a glucose polymer with alpha 1,4 linkages and alpha 1,6 branches, but the branches are not nearly as frequent as in glycogen.

Front 37

Starch is

Back 37

Starch is a mixture of amylose and amylopectin.

Front 38

Cellulose is a

Back 38

Cellulose is a polymer of glucose, but instead of having units linked alpha 1,4, cellulose has the units linked beta 1,4.

Front 39

Ruminant animals, such as cows, have bacteria in their rumens (specialized stomachs) that contain the enzyme

Back 39

Ruminant animals, such as cows, have bacteria in their rumens (specialized stomachs) that contain the enzyme cellulase.

Front 40

Cellulase can break the

Back 40

Cellulase can break the beta 1,4 bonds between the glucoses in cellulose and provide energy to cows.