Carbohydrates Flashcards
What are carbohydrates
all ring structures
hydroxyl and hydrogen groups off carbons
Hydrated carbon (Cn(H2O)n)
Carbohydrates are polymers
What are the key isomers of glucose?
alpha glucose
below
beta glucose
above
how is a disaccharide made?
condensation reaction of two monosaccharides
water released
What is the reaction to break a polymer
hydrolysis reaction
What is an isomer
different structural formula, same molecular formula
What is maltose made of
two alpha glucose molecules
What are the uses of maltose?
germinating seeds use maltose for energy
animals convert starch to maltose to absorb energy easier
What is sucrose made of
alpha glucose and fructose
What is lactose made of?
beta glucose and galactose
What polymers have alpha glucose as its monomer?
amylose(starch)
amylopectin(starch)
glycogen
What polymers have beta glucose as its monomer?
cellulose
What are the covalent bonds in starch?
alpha 1,4 glycosidic bonds
What are the covalent bonds in glycogen?
alpha 1,4 and 1,6 glycosidic bonds
What are the covalent bonds in cellulose?
beta 1,4 glycosidic bonds
What is the structure of amylose?
unbranched polymer
molecules spiral making it compact for storage
What is the structure of amylopectin?
branched polymer
branched chains have many terminals so glucose molecules can be broken off rapidly when energy needed
crystalline structure
What is the structure of glycogen
highly branched
spherical shape
What is the structure of cellulose?
linear chain
alternating orientation = each beta glucose is rotated 180° alternating hydrogen bonds to for between hydroxyl group of adjacent chains
hydrogen bonds = forming microfibrils which provide strength and rigidity
What is the function of amylose
storage for glucose for respiration
storage in plants
releases glucose over a long period of time
insoluble - doesn’t effect water potential
What is the function of amylopectin
releases glucose for cellular respiration rapidly when needed
What is the function of glycogen
can be broken down very quickly
high metabolic rate
storage in animals and fungi
insoluble = doesn’t effect water potential
What is the function of cellulose
plant cell walls = structural molecules
helps plant cell maintain its shape
flexibility = cellulose fibres are flexible allowing the cell wall to expand as it grows
protection = protects ell from mechanical damage and pathogens
support
What is the test for starch
add iodine
will turn from yellow/orange to blue/black
How do you test for reducing sugars?
(all monosaccharides and glucose)
add Benedict’s
heat in water bath at 80°C for 5 minutes
will turn from blue to orange/red/green
more precipitate = higher concentration of reducing sugar
