carbohydrates Flashcards
function of amylose
-stores glucose I plants for respiration
what are the molecules in amylose?
-polymer of alpha glucose molecules, joined by 1-4 glycosidic bonds
structure of amylose
-unbranched
-compact so it stores lots of glucose in a small space
-large so the polymer can’t cross the cell membrane by diffusion
-soluble in water
-twists into complex helix with hydrogen bonds
function of amylopectin
stores glucose in plants for respiration
what are the molecules in amylopectin?
-alpha glucose molecules joined by 1-4 and 1-6 glycosidic bonds
structure of amylopectin
-branched so hydrolysis occurs more rapidly
-compact (due to helix) to store lots of glucose in a small space
-large so the polymer can’t cross the membrane
-insoluble in water so doesn’t affect osmosis
how do you draw an alpha caucuses molecule?
-draw hexagon with oxygen at top right point and carbons at others
-carbon 6 extends from carbon 5
-C1-C4 have H and OH, H must be above Oh on C1
-C5 has only H
-C6 has OH and H²
how do you draw a beta glucose molecule?
-draw hexagon with oxygen at top right point and carbons at others
-carbon 6 extends from carbon 5
-C1-C4 have H and OH, OH must be above H on C1
-C5 has only H
-C6 has OH and H²
3 examples of hexose sugars (6 carbons)
glucose, galactose, fructose
what is a pentose sugar?
has 5 carbons, eg ribose
how do disaccharides form between glucose
-condensation reaction
-glycosidic bond
-molecule of water produced (H²O removed)
how do you form sucrose, lactose and maltose?
sucrose- glucose and fructose
lactose-glucose and galactose
maltose-alpha glucose and glucose
3 properties of glucose
-water soluble-contains large amount of hydroxyl groups
-polar-small negative charge on oxygen, small positive charge on hydrogen
-induces osmosis-if cell contains lots of soluble glucose
what are the 3 types of polysaccharide?
starch-amylose and amylopectin
cellulose
glycogen
what is the function of cellulose?
a major part of cell surface membranes in plants
what are the molecules of cellulose?
-1-4 glycosidic bond where every second beta glucose flips
-weak intermolecular forces between layers held by hydrogen bonds
what is the structure of cellulose?
-unbranched to create straight chain with layers
-mechanically very strong due to huge number of bonds (inflexible)
-cellulose cell wall must resist force of cell content pushing against it
-high tensile strength
-insoluble in water
cellulose-what are micro and macrofibrils
-microfibril made when cellulose chains group together
-macrofibril made when microfibrils group together
-cellulose fibre formed when macrofibrils group together
plant cell wall formed by cellulose fibres
function of glycogen
-storage form of glucose
-found in liver muscle tissue
structure of glycogen
-very branched chains so lots of ends for hydrolysis-rapid break down is necessary for respiring and energetic animals
-insoluble so does not induce osmosis
-large molecule so cannot diffuse out of the cell
-short branches allow more energy storage
molecules of glycogen
-connected mostly by 1-4 bonds
-some branches joined by 1-6 glycosidic bonds
is sucrose non reducing
yes
