carbohydrates

Question 1

monosaccharides

Answer 1

simple sugars, consist of a single polyhydroxy aldehyde or ketone unit
example- D-glucose

Question 2

oligosaccharides

Answer 2

short chains of monosaccharide units, or residues, joined by glycosidic bonds

Question 3

disaccharides

Answer 3

oligosaccharides with two monosaccharide units
example- sucrose (D-glucose and D- fructose)

Question 4

polysaccharides

Answer 4

sugar polymers with 10+ monosaccharide units
ex. cellulose (linear), glycogen (branched)

Question 5

monosaccharides sterochem

Answer 5

d isomers will have the alcohol on the right while l isomers will have the alcohol on the left (fischer projection)

Question 6

properties of monosaccharides

Answer 6

colorless crystalline solid, freely soluble in water but not non-polar solvents, unbranched carbon chains, usually end in “-ose”

Question 7

epimers

Answer 7

type of diastereomers where only 1 carbon has different stereochemistry

Question 8

what are some aldoses and ketoses you need to recognize?

Answer 8

D-glyceraldehyde, D-erythrose, D-ribose, D-arabinose, D-xylose, D-glucose, D-mannose, D-galactose, dihydroxyacetone, D-erythulose, D-ribulose, D-xylulose, D-fructose

Question 9

in aqueous solutions, aldotetroses and all monosaccharides with 5+carbons are predominantly in their

Answer 9

cyclic form

Question 10

the cyclic form is …..

Answer 10

hemiacetal or hemiketal

Question 11

furanose

Answer 11

5-membered ring

Question 12

pyranose

Answer 12

6-membered ring

Question 13

both the furanose and pyranose forms have a __ or __-anomer

Answer 13

a and B

Question 14

the a-anomer has the anomeric -OH group on the _____ side as the C6 group

Answer 14

trans

Question 15

the B-anomer has the anomeric -OH group on the _____ side as the C6 group

Answer 15

cis

Question 16

what monosaccharides come together to form sucrose?

Answer 16

glucose and fructose

Question 17

what monosaccharides come together to form lactose?

Answer 17

galactose and glucose

Question 18

what monosaccharides come together to form maltose?

Answer 18

two glucoses

Question 19

glycosides

Answer 19

thermodynamically unstable, but kinetically stable; energy input needed to form

Question 20

disaccharides

Answer 20

condensation reaction of an alcohol and hemiacetal

Question 21

naming dissaccharides

Answer 21

1) list configuration of the anomeric carbon on the left most monosaccharide
2) name 1st non-reducing monosaccharide; include D/L configuration; include whether it is in its pyranosyl or furanosyl
3) in parenthesis give the location of the glycosidic bond
4) repeat steps for next sugars in chain

Question 22

polysaccharides (glycans)

Answer 22

sugar polymers; most carbohydrates are in this form; infinite polymers meaning could build onto them forever; very water soluble; possible to have multiple branch points; homopolysaccharides use only 1 type of monosaccharide in their chain-> used for energy storage and structural support; heteropolysaccharides use 2+ types of monosaccharides-> used for extracellular support

Question 23

starch

Answer 23

energy storage in plants; composed of amylose and amylopectin; broken down from the non-reducing end to give glucose

Question 24

amylose

Answer 24

unbranched glucose chain with a 1-4 glycosidic bonds

Question 25

amylopectin

Answer 25

branched glucose chain (branches every 24-30 residues)

Question 26

glycogen

Answer 26

long-term energy storage for animals and fungi; polymer of (a 1-4) linked D-glucose with branching (a 1-6) every 8-12 residues

Question 27

cellulose

Answer 27

structural component of plants; most animals lack the enzymes to break this down; unbranched chain of (B 1->4) linked D-glucose; neighboring groups are flipped 180 (allows for increased hydrogen bonding)