carbohydrate

what is the bond for carbohydrate?

glycosidic bond

what components make up carbohydrate?

carbon, hydrogen, oxygen

what are the types of carbohydrate?

monosaccharide, disaccharide, polisaccaride

examples of monosaccharide (GFG)

glucose, fructose, galactose

what are the properties of monosaccharide?

1. reducing sugar

2. readily soluble in water

3. exhibit alpha/beta isomerism

what does reducing sugar mean?

presence of carbonyl group (C=O)

what does readily soluble in water mean?

small + multiple hydroxyl group (OH) that forms H bonds with water

what does exhibit alpha/beta isomerism mean? state where the OH group is

1. alpha

   • OH group at the bottom

2. beta

   • OH group at the top

how is disaccharide formed?

condensation reaction; 1 molecule of water is lost — glycosidic bond is formed

how is disaccharide broken down?

hydrolysis reaction; 1 molecule of water is gained

examples of disaccharide (SML), state their monomers

1. sucrose

   • alpha glucose

   • beta fructose

2. maltose

   • alpha glucose X2

3. lactose

   • glucose

   • galactose

bond for maltose

alpha (1—4) glycosidic bond

bond for sucrose

alpha (1—2) glycosidic bond

what are the properties of disaccharide?

1. reducing sugar (except sucrose)

2. readily soluble in water

examples of polysaccharides

1. starch

2. glycogen

3. cellulose

what type of monomer is for:

1. starch

2. glycogen

3. cellulose

1. alpha-glucose monomer

   • amylopectin

   • amylase

2. alpha-glucose monomer

3. beta-glucose monomer

what bond between starch?

1a. amylopectin

• alpha (1—4) glycosidic bond

• alpha (1—6) glycosidic bond

1b. amylase

• alpha (1—4) glycosidic bond

what bond between glycogen?

1. alpha (1 → 4) glycosidic bond

2. alpha (1 → 6) glycosidic bond

what bond between cellulose?

beta- (1 → 4)  glycosidic bond

which bonds are branched within monomers

• alpha (1 → 4) glycosidic bond

• beta- (1 → 4)  glycosidic bond

which bonds are branched @branched points

alpha (1 → 6) glycosidic bond

what are the properties for starch?

1. Amylopectin 

• Helical + branched

2. Amylose 

• Helical + unbranched

3. Monomers are same orientation 

what are the properties for glycogen

1. More extensively branched than amylopectin 

2. Monomers are same orientation

what are the properties for cellulose

1. Monomers are rotated 180 wrt to each other 

2. Long straight chain 

3. Unbranched

out of starch, glycogen and cellulose, which is involved in interchain H bonding?

cellulose:

OH groups are projected outwards in both directions, this allows for interchain H bonding.

what purpose does interchain H bonding for cellulose serve?

forms microfibrils

what makes starch + glycogen a good storage molecule?

1. insoluble

2. branched

3. compact energy store

what makes starch + glycogen insoluble?

1. Large 

2. Has few OH groups to be involved in H bonding with water

   • intramolecular bonding 

why is being branched for stomach and glycogen good?

• Has many branched ends for hydrolytic enzymes to work on

• Can hydrolyze more α- glucose monomers to form more ATP for energy 

• Release more glucose 

what makes starch + glycogen have compact energy storage?

• Due to monomers being bent in 1 direction, linked to its adjacent molecule, more α- glucose monomers can be packed

what makes cellulose a good structural molecule?

1. insoluble

2. high tensile strength

3. cannot be hydrolysed

why is cellulose insoluble

• Has few OH groups to be involved in H bonding with water

• Most OH groups are involved with interchain H bonding 

why does cellulose have high tensile strength?

1. Porous 

• Allow movement of substances in and out of cell 

2. High tensile strength

• Prevents wall from bursting due to osmosis stress 

for storage molecule VS structural molecule, what is the difference between both OH groups involved with interchain H bonding?

storage: intrachain H bonding

structural: interchain H bonding