module 2 - carbohydrates Flashcards
what is a single sugar unit called?
a monosaccahride
what is a carbohydrate compsed of?
carbon, oxygen,hydrogen
what are 2 monosaccahrides joined together called?
a disaccahride polymer
what are multiple monosaccahrides joined together called?
a polysaccahride
what type of monosaccahride is glucose?
hexose monosaccahride as it contains 6 carbons
what are the 2 types of glucose and what are their structures?
alpha glucose:
CH3OH
|
c——-o H
/ \ /
c c
\ / \
c——c OH
beta glucose:
CH3OH
|
c——-o OH
/ \ /
c c
\ / \
c——c H
how do alpha and beta glucose differ from each other?
The hydroxyl group (OH) on carbon 1 is in opposite positions
This affects the structure and properties of the polysaccarides when it bonds
how does a disaccharide form?
via the condensation of two monosaccharide
the hydroxyl group on one reacts with the hydrogen on the other to produce H2O
a glycosidic bond forms
what bond forms during the condensation of 2 monosaccharides?
a glycosidic bond
how is lactose made?
glucose + galactose
how is maltose made?
glucose + glucose
how is sucrose made?
glucose + fructose
what is a pentose sugar?
sugar containing only 5 carbons e.g fructose
what are the properties of starch?
> Compact
Chemical energy store
Easily digestible
Made of amylose (mainly, 1-4 glycosidic bonds) and amylopectin (1-4 and some 1-6 glycosidic bonds)
Insoluble does not create a water potential gradient (doesn’t cause water to enter cells by osmosis which would make them swell up)
what are the properties of amylose?
> joined by 1-4 glycosidic bonding
compact - easily stored and released (twists into a helix)
metabolically inactive
held together by hydrogen bonds
what are the properties of amylopectin?
> joined by 1-6 and 1-4 glucosidic bonds making it even more compact due to more bends
indelible - do not effect water potential
Branches gives ‘free ends’ so glucose can be added or released quickly
what are the properties of glycogen?
> short, branched chains of alpha glucose
joined by 1-4 and 1-6 glycosidic bonds = compact and ideal for storage
Branches gives ‘free ends’ so glucose can be added or released quickly
What is the function of glycogen?
Main energy store in animals
Stores soluble glucose that affects water potential as insoluble polysaccharide until needed
what are the properties of glycogen?
> unbranched chain of beta glucose
forms beta pleated sheets as every other glucose molecule is orientated 180˚
1-4 glucosidic bonding
chains are linked by hydrogen bonds between functional groups forming strong fibres called microfibrils (compact)
microfibrils join to make macrofibrils, which combine to make fibres
what is the function of cellulose?
> important part of our diet as it is very hard to breakdown so if the fibre necessary for a healthy digestive system
Cellulose provides structural support for cells
how is a disaccharide broken?
hydrolysis
