organic substances contain carbon, e.g. carbs, lipids and proteins
inorganic substances:do not contain carbon e.g. water
water:
70% body mas of most organisms
dipolar due to hydrogen positive and oxygen negative in the sharing of an electron
hydrogen bonds connect the water molecules causing high sphc and high latent heat of vaporisation, high surface tension, high density, excellent solvent properties.
specific heat capacity: the amount of energy required to increase the temperature of 1g of a substance by 1deg.
latent heat of vapourisation: the amount of heat energy required to turn a given quantity of liquid into a gas.
molecules that have dipoles are attracted to the charges on the water molecules and do spread out easily.
Carbohydrates:
contain carbon, hydrogen and oxygen.
1c:2H:10
carbs with small molecules are sugars and taste sweet
carbs with large molecules are called polysaccharides and do not taste sweet.e.g cellulose.
3c-triose
5c-pentose
6c-hexose
glucose-hexose-resp-carb tranpsport
fructose-hexose-nectar- with glucose forms sucrose
galactose-hexose-combined to glucose forms lactose
ribose-pentose-component of rna
deoxyribose-pentose-component of dna
Monosaccharides: carbs whose molecules are single sugars
disaccharides:carbs that contain two monosacchardies, sugars, sweet soluble
a condensation reaction joins two glucose molecules and this forms a glcosidic bond. this can be broken by hydrolysis
maltose-glucose+glucose-provides energy from breakdown of starch
sucrose-glucose+fructose-carbs are transported in plants
lactose-glucose+galactose- energy soruce in milk
Polysacchardes:many monosaccharides, large not soluble
starch-amylose+amylopectin
starch curls into a spiral they are held in shape by hydrogen bonds
glycogen has a similar structure to amylopectin, storgae of carbohydrates in animals.
cellulose is a polymer of beta glucose, lie parralell to each other forming a microfibril.
Lipids:
fats, oils and waxes.
contain carbon hydrogen and oxygen, they are insoluble in water
Triglyceride: glycerol and three fatty acids linked by ester bonds.
saturated fatty acid- two hyydrogen bonds
unsaturated two or more carbon atoms have hydrogen attached(double bond)
roles of triglycerides:
energy store
bouyancy
protection
waterproofing
thermal insulation
useful as canbe stored as droplets inside cells.
insultion against heat loss
Phospholipids:
glycerol and two fatty acid chains and a phosphate group, fatty acids are hydrophobic and face inwards in a bilayer.
Phophate is hydrophillic
Proteins:
polymer made of amino acids
carbon, hydrogen, oxygen and nitrogen.
amino acid molecules, contains an amino groupand a carboxyl group
20 naturally occuring amino acid
join, condensation
linked by a peptide bond
hydrolysis splits
Primary structure: sequence of amino acids
secondary structure: first 3d structure , strand or helix
tertiary structure: complex 3d shape
quaternary structure: arrangement of polypeptides.
ionic-hydrogen and disulphide bonds.
Insulin: a globular protein, soluble in water, a hormone made in the pancreas, acts on the liver cells,
collagen:insoluble protein, fibrous, collagen fibril, found in skin, teeth, bones, tendons.
nucleic acids: polymers made of nucleotides.
a nucleotide consists of an organic base,pentose sugar and a phosphate group.
the sugar is either ribose or deoxyribose
5 bases: adenine, thymine, guanine, cytosine, uracil
a-t
g-c
connected by two hydrogen bonds
RNA: 1 polynuecletide strand
contains ribose
uracil replaces thymine
DNA replication:
semi-conservative replication
half of the original molecule is conserved in the new one.
controlled by enzymes e.g. DNA polymerase
1) double helix unwinds, hydrogen bonds break, strand separate
2)fre nucleoides present pair up with exposed complimentary base on each strand, hydrgoen bonds
3)phosphate group fors a bond with the sugar, to form a new strand.
DNA coding for protein synthesis:
the sequence of bases in a DNA molecule in the nucleus determines the sequence of amino acids in the protein made by the cytoplasm.
gene:length of dna that codes for 1 polypeptide
this takes place during interphase.
3 bases code for 1 amino acids, called an anitcodon
two or more different anticodons represent 1 amino acid.
Proten synthesis:
stage 1= transcription, stage 2 = translation
1) dna molecule unwind, exposing bases
2) rna moves into their complementary bases
3)mrna is formed
4) mrna break away from the dna and moves out of the nucles into the cytoplasm.
remeber u replaces T
A-U
Translation:
mrna held by ribosomes, trna binds
2 trna bind, 1 to each codon
the two amino acids carrid by trna bind
the first trna leaves, a third trna brings its amino acid to the growing chain
this process continues untill a stop codon is reached. then the peptide chain leaves the ribosome
Human genome prject:
1990, find the base sequences of all dna in the nucleusof a human cell. be able to understand more how genes affect our behaviour, better treatments for diseases, easier to develop drugs, can see if a genetic disease had been passed on.
Biochemical tests:
test for how positive results
starch add iodine in potassium iodide solution blue-black colour
reducing sugar add benedicks solution, boil then stop brick red precipitate
non-reduc sugar boil+ hydroclhoric acd, add weak alkali, test for reduc sugar
protein add biuret reagent, cppr dulphte sol+potasum hydrx violet clr
Enzymes:
these are catalysts that are not altered by reactions
they are globular proteins,hydrogen ionic and disulphide bond hold tertiary structure.
enzyme molecules have active sites, this is where the substrate can bind
work of enzymes:
activation energy, enzymes provide an alternative pathway of lower activation energy.
affect of temp on enzymes:
high temps, cause high kinetic energy and molecules move around faster. and bump into each other with more energy.
high temps also cause enzymes to loose their shape, denatured and converison cannot take place. there is an optimum temp.
affect of pH
most have an optimum of around neutral,
affect of enzyme conc' and substrate conc'
as enzyme conc' increases so does rate of reaction it it plateaus out.
as substrate concetration increase so does the rate of reaction untill it plateaus out.
Inhibitors:
slows down the rate at with the reaction takes place.
enzyme inhibitors work by binding to the enzyme.
active site directed binds into the active site permanently preventing a substrate.
non- active site directed binds with enzyme and this changes the shape of the active site.
inorganic substances:do not contain carbon e.g. water
water:
70% body mas of most organisms
dipolar due to hydrogen positive and oxygen negative in the sharing of an electron
hydrogen bonds connect the water molecules causing high sphc and high latent heat of vaporisation, high surface tension, high density, excellent solvent properties.
specific heat capacity: the amount of energy required to increase the temperature of 1g of a substance by 1deg.
latent heat of vapourisation: the amount of heat energy required to turn a given quantity of liquid into a gas.
molecules that have dipoles are attracted to the charges on the water molecules and do spread out easily.
Carbohydrates:
contain carbon, hydrogen and oxygen.
1c:2H:10
carbs with small molecules are sugars and taste sweet
carbs with large molecules are called polysaccharides and do not taste sweet.e.g cellulose.
3c-triose
5c-pentose
6c-hexose
glucose-hexose-resp-carb tranpsport
fructose-hexose-nectar- with glucose forms sucrose
galactose-hexose-combined to glucose forms lactose
ribose-pentose-component of rna
deoxyribose-pentose-component of dna
Monosaccharides: carbs whose molecules are single sugars
disaccharides:carbs that contain two monosacchardies, sugars, sweet soluble
a condensation reaction joins two glucose molecules and this forms a glcosidic bond. this can be broken by hydrolysis
maltose-glucose+glucose-provides energy from breakdown of starch
sucrose-glucose+fructose-carbs are transported in plants
lactose-glucose+galactose- energy soruce in milk
Polysacchardes:many monosaccharides, large not soluble
starch-amylose+amylopectin
starch curls into a spiral they are held in shape by hydrogen bonds
glycogen has a similar structure to amylopectin, storgae of carbohydrates in animals.
cellulose is a polymer of beta glucose, lie parralell to each other forming a microfibril.
Lipids:
fats, oils and waxes.
contain carbon hydrogen and oxygen, they are insoluble in water
Triglyceride: glycerol and three fatty acids linked by ester bonds.
saturated fatty acid- two hyydrogen bonds
unsaturated two or more carbon atoms have hydrogen attached(double bond)
roles of triglycerides:
energy store
bouyancy
protection
waterproofing
thermal insulation
useful as canbe stored as droplets inside cells.
insultion against heat loss
Phospholipids:
glycerol and two fatty acid chains and a phosphate group, fatty acids are hydrophobic and face inwards in a bilayer.
Phophate is hydrophillic
Proteins:
polymer made of amino acids
carbon, hydrogen, oxygen and nitrogen.
amino acid molecules, contains an amino groupand a carboxyl group
20 naturally occuring amino acid
join, condensation
linked by a peptide bond
hydrolysis splits
Primary structure: sequence of amino acids
secondary structure: first 3d structure , strand or helix
tertiary structure: complex 3d shape
quaternary structure: arrangement of polypeptides.
ionic-hydrogen and disulphide bonds.
Insulin: a globular protein, soluble in water, a hormone made in the pancreas, acts on the liver cells,
collagen:insoluble protein, fibrous, collagen fibril, found in skin, teeth, bones, tendons.
nucleic acids: polymers made of nucleotides.
a nucleotide consists of an organic base,pentose sugar and a phosphate group.
the sugar is either ribose or deoxyribose
5 bases: adenine, thymine, guanine, cytosine, uracil
a-t
g-c
connected by two hydrogen bonds
RNA: 1 polynuecletide strand
contains ribose
uracil replaces thymine
DNA replication:
semi-conservative replication
half of the original molecule is conserved in the new one.
controlled by enzymes e.g. DNA polymerase
1) double helix unwinds, hydrogen bonds break, strand separate
2)fre nucleoides present pair up with exposed complimentary base on each strand, hydrgoen bonds
3)phosphate group fors a bond with the sugar, to form a new strand.
DNA coding for protein synthesis:
the sequence of bases in a DNA molecule in the nucleus determines the sequence of amino acids in the protein made by the cytoplasm.
gene:length of dna that codes for 1 polypeptide
this takes place during interphase.
3 bases code for 1 amino acids, called an anitcodon
two or more different anticodons represent 1 amino acid.
Proten synthesis:
stage 1= transcription, stage 2 = translation
1) dna molecule unwind, exposing bases
2) rna moves into their complementary bases
3)mrna is formed
4) mrna break away from the dna and moves out of the nucles into the cytoplasm.
remeber u replaces T
A-U
Translation:
mrna held by ribosomes, trna binds
2 trna bind, 1 to each codon
the two amino acids carrid by trna bind
the first trna leaves, a third trna brings its amino acid to the growing chain
this process continues untill a stop codon is reached. then the peptide chain leaves the ribosome
Human genome prject:
1990, find the base sequences of all dna in the nucleusof a human cell. be able to understand more how genes affect our behaviour, better treatments for diseases, easier to develop drugs, can see if a genetic disease had been passed on.
Biochemical tests:
test for how positive results
starch add iodine in potassium iodide solution blue-black colour
reducing sugar add benedicks solution, boil then stop brick red precipitate
non-reduc sugar boil+ hydroclhoric acd, add weak alkali, test for reduc sugar
protein add biuret reagent, cppr dulphte sol+potasum hydrx violet clr
Enzymes:
these are catalysts that are not altered by reactions
they are globular proteins,hydrogen ionic and disulphide bond hold tertiary structure.
enzyme molecules have active sites, this is where the substrate can bind
work of enzymes:
activation energy, enzymes provide an alternative pathway of lower activation energy.
affect of temp on enzymes:
high temps, cause high kinetic energy and molecules move around faster. and bump into each other with more energy.
high temps also cause enzymes to loose their shape, denatured and converison cannot take place. there is an optimum temp.
affect of pH
most have an optimum of around neutral,
affect of enzyme conc' and substrate conc'
as enzyme conc' increases so does rate of reaction it it plateaus out.
as substrate concetration increase so does the rate of reaction untill it plateaus out.
Inhibitors:
slows down the rate at with the reaction takes place.
enzyme inhibitors work by binding to the enzyme.
active site directed binds into the active site permanently preventing a substrate.
non- active site directed binds with enzyme and this changes the shape of the active site.
