Chapter 3 - carbohydrates

Question 1

Carboxyl acid

Answer 1

It will tend to lose a hydrogen. example: the deprotonated form of formic acid (shown) becomes formate. Also acetic acid becomes acetate.

Question 2

glucose structure

Answer 2

In living organisms, takes on dextrorotatory structure (D-glucose). Note that C-1 is chiral center, where OH pointing up is beta-glucose and OH pointing down is alpha-glucose. The direction of OH at C-4 distinguishes between glucose and galactose.

Question 3

lactose

Answer 3

disaccharide of glucose and galactose, where the OH group on the galactose is up, so linkage is beta 1,4 glycosidic

Question 4

structure of galactose

Answer 4

a stereoisomer of glucose. Has OH and H switched at number 4 carbon

Question 5

structure of ribose

Answer 5

5-carbon sugar with 3 OH groups and 1 CH₂OH

Question 6

Sulfhydryl

Answer 6

placeholder: “this will create an important type of bond”

Question 7

suffix for a sugar

Answer 7

“ose”

Question 8

Stereoisomers

Answer 8

isomers that have a difference in how the attached groups are arranged in space

Question 9

solubility of carbohydrates

Answer 9

will be soluble because they contain many hydroxyl groups, therefore charged

Question 10

maltose

Answer 10

the sugar present in apples. A disaccharide of 2-alpha-D-glucose with link between 1 and 4 carbons: alpha 1,4 glycosidic linkage

Question 11

sucrose

Answer 11

a common disaccharide of glucose and fructose with Alpha, 1-4 glycosidic linkage. Click save

Question 12

Hydroxyl functional group

Answer 12

“hydroxyl is kind of like water” because of the high electronegativity of O, it is polar, and thus, is soluble in water. Can make an alcohol, or carboxylic acid (with carbonyl)

Question 13

Beta glycosidic linkage

Answer 13

where the OH is in the up position at carbon 1

Question 14

Monosaccharides

Answer 14

simple sugars including 3, 5, 6-carbon sugards. Typically energy storage involves a 6-carbon sugars (e.g. glucose)

Question 15

lactase

Answer 15

enzyme for splittling lactose present at birth which gets turned off after birth, leading to lactose intolerance

Question 16

Hydrolysis reaction

Answer 16

Also known as hydration. Removes H attached to one monomer and OH attached to the other. In order to split the ploymer, one water molecule is consumed per breaking off a subunit. This is how we digest food

Question 17

Phosphate

Answer 17

PO₄^2- : Important functional group in biology. The conjugate base of phosphoric acid.

Question 18

Ketoses

Answer 18

Ketones that are sugars with 3, 5, or 6 carbons

Question 19

Methyl

Answer 19

Simple functional group of CH₃

Question 20

Chiral molecule rotated to the right

Answer 20

dextrorotatory

Question 21

Carbonyl

Answer 21

types of carbonyls: aldehyde or ketone

Question 22

Suffix for deprotonated form of an acid

Answer 22

“ate”

Question 23

Carbohydrates (general definition)

Answer 23

Molecules containing C, H, and O in 1:2:1 ratio (CH₂O)_n

excesswill be stored as fat

Question 24

Chiral molecule rotated to the left

Answer 24

levorotatory

Question 25

B-glucose

Answer 25

hydroxyl has OH at C-1 pointing up

Question 26

hydrocarbons (polarity)

Answer 26

non-polar because hydrogen and carbon have similar electronegativities ( 2.1-H and 2.5-C)

Question 27

Alpha glycosidic linkage

Answer 27

where the OH is in the down position at carbon 1

Question 28

Dehydration synthesis

Answer 28

Known as condensation. Linking of monomer subunits releases a water molecule (one monomer loses OH and H from the other). Example: linking of fatty acids to glycerol

Question 29

Chiral molecule

Answer 29

A molecule that has a mirror image. Example: D-sugars and L-amino acids. Requires that C has 4 distinct groups around it.

Question 30

Solubility of charged molecules

Answer 30

tends to be soluble (e.g. OH^-)

Question 31

Structure of deoxyribose

Answer 31

Same as ribose, except missing O at C-2

Question 32

Fructose

Answer 32

Structural isomer of glucose, where carbonyl is at C-2 (instead of C-1)

Question 33

Enantiomers

Answer 33

type of stereoisomer where two isomers are mirror images of each other

Question 34

Structural isomers

Answer 34

Aka constitutional isomers. They have a difference in the structure of carbon backbone (arrangement of atoms)

Question 35

Polymer

Answer 35

long molecule of linked monomer subunits. All macromolecules are polymers

Question 36

Structure of 6-carbon sugars in water

Answer 36

Ring structure

Question 37

hexose isomers

Answer 37

sugars with 6 carbons

Question 38

Catalysis

Answer 38

process of carrying out dehydration reaction within cells by enzymes

Question 39

suffix for enzymes

Answer 39

“ase”

Question 40

Alpha glucose

Answer 40

hydroxyl group (OH) pointing down at C-1

Question 41

Amino

Answer 41

the amino group acts as a base. Example: R-NH₂ → R-NH₃

Question 42

Enzyme

Answer 42

usually a protein that acts as a biological catalyst. Example: Kinase which “moves around phosphate groups”

Question 43

starch in plants

Answer 43

a large polysaccharide chain. There is a branch point at carbon 6 allowing for “branching” polysaccharides with Alpha, 1-6 glycosidic linkages.

Question 44

contents of potato

Answer 44

20% amylose

80% amylopectin (branchy)

Question 45

starch in animals

Answer 45

stored as glycogen in liver and muscles. It is a little longer, and a little more “branchy”

Question 46

cellulose

Answer 46

Found in plant cell walls. Has a beta, 1-4 glycosidic linkage chaining together B-glucose monomers

Question 47

Chitin

Answer 47

a modified polysaccharide found in:

1. fungi cell walls
2. exoskeletons of many invertebrates

Question 48

peptidoglycan

Answer 48

Structural support bacterial cell walls
Two types of monosaccharides (N-acetylglucosamine & N-acetylmuramic acid)
Linked by Beta - 1,4 glycosidic linkages acetylmuramic acid linked to chain of amino acids and peptide bond link amino acid chains of adjacent strands