mod7 monosaccharides properties + extra

describe taste of monosaccharides:

used in sweeteners

explain bonding of monosaccharides:

capable of extensive hydrogen bonding because of many OH groups around the structure

explain properties of monosaccharides:

solids at room temperature

have high MP and BP compared to ordinary alcohols

very soluble in water

what are open chain monosaccharides used for:

studying structure and stereochemistry

why do most monosaccharides cyclise:

carbonyl + alcohol groups form to produce a hemi-acetal/ketal

name the prefixes for naming cyclic monosaccharides:

five carbon ring is -furan-

six carbon ring is -pyran-

explain the equilibrium between open and cyclised monosaccharides

equilibrium strongly favours the cyclic form, therefore prefixes aren’t necessary when naming

monosaccharides exist in cyclic form most of the time

explain what happens to formation during cyclisation:

anomer’s form

aldehydes oxygen is pushed either above the plane or below the plane

what is anomeric carbon:

the carbon attached to carbonyl group of anomer

name the important monosaccharides:

glucose

galactose

fructose

D-ribose and D-deoxyribose

explain ribose and deoxyribose:

RNA and DNA building blocks

cyclised 5 sided rings (furanoses)

name the 3 reactions of monosaccharides:

oxidation

esterification

glycosidic linkage

explain oxidation of a monosaccharide:

because they have aldehyde groups can be oxidised by Benedict or tollens reagent (oxidising agents)

known as reducing sugars because they reduce something else

explain esterification of a monosaccharide:

hydroxy groups act like alcohol groups (react with acids to make esters)

carboxylic acid + alcohol → ester + water

explain glycosidic linkage:

reaction between 2 monosaccharides will produce a glycosidic bond that joins the molecules together

glycosidic bond exists between the OH of anomeric carbon and OH on neighbouring carbon molecule

forms disaccharides

name polysaccharide properties:

too large to be water soluble

thickening agent

tasteless

not reducing sugars

name 3 important polysaccharides:

starch

glycogen

cellulose

explain starch:

how glucose is stored in plants for later use

explain glycogen;

energy reserve carbohydrate in animals

stored in liver and muscles

explain cellulose:

plant skeletal