2.1.2 - biological molecules Flashcards
what elements are carbohydrates made of
carbon
hydrogen
oxygen
what elements are lipids made of
carbon hydrogen oxygen (same as carbs)
what elements are proteins made of
carbon
hydrogen
oxygen
nitrogen
sulfur
what elements are nucleic acids made of
carbon
hydrogen
oxygen
nitrogen
phosphorus
what are monomers
single subunits of life
how are polymers formed
by combining monomers using covalent bonds
what is a condensation reaction
the formation of polymers from monomers
what is the by-product of condensation
water
what do the condensation of amino acids produce
proteins
what does the condensation of monosaccharides froduce
disaccharides
what does the condensation of many disaccharides produce
polysaccharides
what does the condensation of fatty acids and monoglycerides produce
lipids
what is a hydrolysis reaction
the break down of large biological molecules into smaller molecules
what does the hydrolysis reaction require
water
hydrolysis of proteins produces
amino acids
hydrolysis of carbs produce
di/monosaccharides
hydrolysis of lipids produces
fatty acids and monoglycerides
what is a pentose monosaccharide
a monosaccharide with 5 carbons
what is a hexose monocsaccharide
a monosaccharide with 6 carbons
what kind of monosaccharide is ribose
pentose
what kind of monosaccharide is glucose
hexose
how is deoxyribose different from ribose
an oxygen is lost from carbon-2
alpha and beta glucose are isomers. what are isomers
have the same molecular formula but different arrangement of atoms in space
glucose + glucose
maltose
glucose + fructose
sucrose
glucose + galactose
lactose
function of sucrose
common table sugar
function of lactose
a sugar found in milk
what kind of bonds join together monosaccharides to form polysaccharides
glycosidic bonds
what is a glycosidic bond
when OH groups from neighbouring monosaccharides undergo a condensation reaction to form an O link between the 2 monosaccharides, with water being released.
how do you break a glycosidic bond
a hydrolysis reaction occurs where water is added
functions of starch
- main energy storage material in plants
- broken down into glucose by plants when they need more energy
- acts as a source of food for humans and animals
features of starch
- does not change the water potential in a cell because it is insoluble in water
- made up of amylopectin and amylose which are both alpha-glucose polysaccharides
what is amylopectin
highly branched chain of alpha-glucose monomers
why is amylopectin so accessible to enzymes to release energy
the branched structure leaves more free ends so enzymes can access more of it to release glucose molecules
what is amylose
linear chain of alpha-glucose monomers
what kind of structure of amylose have
a helix structure
what kind of glycosidic bonds are for linear chains of alpha glucose
1,4 glycosidic bonds
what kind of glycosidic bonds are for branches of alpha glucose
1,6 glycosidic bonds
what is the main storage molecule in plants
starch
what is the main storage molecule in animals
glycogen
is amylopectin or glycogen more branched
glycogen
what happens to glycogen when blood glucose levels decrease
glycogen is broken down to release glucose
glucose is soluble in water. Is glycogen also soluble?
no. starch is also insoluble
what monomers is cellulose made of
beta glucose monomers
how does a 1,4 glycosidic bond form between 2 beta glucoses
every alternate beta glucose flips 180 degrees
what stops the linear chains of beta glucoses forming cellulose from spiralling
Hydrogen bonds
how many straight chains of H bonds forms a microfibril
60-70
how many microfibrils make a macrofibril
around 400
functions of cellulose
cell walls of plants are made of cellulose
what is the structure of a triglyceride
glycerol bonded to 3 fatty acid molecules
structure of a glycerol
has 3 hydroxyl groups which are used to bond to the fatty acids
what is the difference between a saturated and non-saturated fatty acid
unsaturated fatty acids have at least 1 double covalent bond between carbon atoms and saturated fatty acids don’t
structure of a phospholipid
glycerol bonded to a phosphate ion and 2 fatty acids
what part of the phospholipid is polar
the phosphate head
is the phospholipid head hydrophobic or philic
hydrophilic
what part of the phospholipid is non polar
the tail
is the phospholipid tail hydrophobic/philic
hydrophobic
what is the phospholipid bilayer
when the heads of the phospholipid position themselves outwards so they touch the water and the tails are on the inside and don’t touch the water
what reaction occurs when fatty acids react together with glycerol
condensation reaction
how many waters are made during esterification
3
what is the name of the process where the fatty acids react with the glycerol to form a triglyceride
esterification
why are triglycerides good for waterproofing
Triglycerides are non polar so they are hydrophobic and don’t dissolve in water
function of triglycerides
- protects organs
- used for waterproofing - eg ducks have oils which coat the feathers
function of phospholipids
used in the cell membrane
what part of the cholesterol is hydrophilic
the hydroxyl group
what part of the cholesterol interacts with the hydrophilic head of the phospholipid
the hydroxyl group (the rest of the group reacts with the fatty acid tails)
how many different amino acids are there
20
what is the general structure of an amino acid
amino group, carboxyl group, r group
what part of an amino acid is the same for every amino acid
amine group and the carboxyl group
what part of the amino acid is different for all 20 amino acids
the R group
what is the name of a bond formed between 2 amino acids
peptide bond
what kind of reaction is a peptide bond formed in
condensation
where does the condensation reaction to form peptide bonds take place
ribosomes
how do you break a peptide bond
by adding water in a hydrolysis reaction
what enzymes breaks peptide bonds
protease
when is a polypeptide considered a protein
when it has folded into its specific 3D shape.
why is water a polar molecule
the oxygen atoms are negatively charged and the hydrogen atoms are positively charged
