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2.1.2: biological molecules Flashcards

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1
Q

what 4 elements are most important in living organisms?

A

carbon, hydrogen, oxygen and nitrogen

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2
Q

how many bonds can carbon atoms form?

A

4 bonds

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3
Q

how many bonds can nitrogen atoms form?

A

3 bonds

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4
Q

how many bonds can oxygen atoms form?

A

2 bonds

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5
Q

how many bonds can hydrogen atoms form?

A

1 bond

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6
Q

what is a covalent bond?

A

a strong bond where 2 atoms share a pair of electrons

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7
Q

what is an ionic bond?

A

one atom in a pair donates an electron to the other. this results in positive and negative ions, held together by opposite charges

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8
Q

what is an ion?

A

an atom/molecule in which the total number of electrons is not equal to the total number of protons

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9
Q

what is a cation and an anion?

A

cation is a positively charged ion while an anion is a negatively charged ion

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10
Q

what are hydrogen bonds?

A

where a slightly negatively charged atom binds to a slightly positively charged hydrogen atom

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11
Q

what elements are present in water?

A

hydrogen and water

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12
Q

what elements are present in carbohydrates?

A

carbon, hydrogen and oxygen

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13
Q

what elements are present in lipids?

A

carbon, hydrogen and oxygen

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14
Q

what elements are present in proteins?

A

carbon, hydrogen, oxygen, nitrogen and sometimes sulfur

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15
Q

what elements are present in nucleic acids?

A

carbon, hydrogen, oxygen, nitrogen and phosphorus

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16
Q

what are calcium ions used for?

A

nerve impulse transmission and muscle contractions

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17
Q

what are sodium ions used for?

A

nerve impulse transmission and kidney function

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18
Q

what are potassium ions used for?

A

nerve impulse transmission and stomatal opening in leaves

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19
Q

what are hydrogen atoms used for?

A

catalysing many reactions and ph regulation by measuring acidity

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20
Q

what are ammonium ions used for?

A

by bacteria to make nitrate ions which are important in the nitrogen cycle

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21
Q

are calcium ions cations or anions?

A

cation

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22
Q

are sodium ions cations or anions?

A

cation

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23
Q

are potassium ions cations or anions?

A

cations

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24
Q

are hydrogen ions cations or anions?

A

cation

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25
Q

are ammonium ions cations or anions?

A

cation

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26
Q

what are nitrate ions used for?

A

the form that plants take up nitrogen and used by plants to make proteins

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27
Q

what are hydrogen carbonate ions made from?

A

to maintain blood plasma ph

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28
Q

what are chloride ions used for?

A

to balance the positive charges of sodium and potassium ions in cells

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29
Q

what are phosphate ions used for?

A

cell membrane formation, the formation of nucleic acids and atp and bone formation

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30
Q

what are hydroxide ions used for?

A

help to catalyse reactions and help ph regulations by measuring the alkalinity

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31
Q

are nitrate ions cations or anions?

A

anion

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32
Q

are hydrogen carbonate ions cations or anions?

A

anion

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33
Q

are chloride ions cations or anions?

A

anion

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34
Q

are phosphate ions cations or anions?

A

anion

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35
Q

are hydroxide ions cations or anions?

A

anion

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36
Q

what is a monomer?

A

a small single molecule, which can join to many other similar molecules (repeating units) to make a polymer

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37
Q

give 2 examples of monomers

A

amino acids and nucleotides

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38
Q

what is a polymer?

A

a large molecule (macromolecule) made up of smaller monomers joined together

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39
Q

give 2 examples of monomers

A

proteins and dna

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40
Q

what happens during a condensation reaction?

A

when 2 molecules join together, involving the removal of water

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41
Q

is a condensation an anabolic or catabolic reaction?

A

anabolic reaction

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42
Q

what is a hydrolysis reaction?

A

whenever a molecule is split apart, involving the addititon of water

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43
Q

is a hydrolysis reaction an anabolic or a catabolic reaction?

A

catabolic reaction

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44
Q

what does polar mean?

A

with and uneven charge distribution across it meaning one part is slightly negative while the other part is slightly positive

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45
Q

what atoms is water made from and how?

A

2 hydrogen atoms covalently bonded to 1 oxygen atom

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46
Q

how is water polar?

A

the oxygen atom has greater number of protons in its nucleus so it exerts a stronger attraction for the shared electrons, meaning the oxygen atom becomes slightly negative and the 2 hydrogen atoms are slightly positive

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47
Q

true or false: water molecules can’t attract each other

A

false. they can because of their polar nature

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48
Q

what are 6 properties of water that make it so important for living organisms?

A

water is a liquid at room temperature, a good solvent, less dense when it it solid, has a high specific heat capacity, a high latent heat and is cohesive

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49
Q

why is water a liquid at room temperature?

A

as molecules move, they continuously make and break hydrogen bonds therefore making it difficult to escape to form gas. therefore it has a highly boiling point and therefore is a liquid at room temperature

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50
Q

what are the advantages of water being a liquid at room temperature?

A

aquatic habitats meaning fish can live underwater, it’s a major component of our cells, the cytoplasm stores water and it is an ideal transport medium

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51
Q

why is water a good solvent?

A

because it is polar, anything polar or is a charge ion can dissolve in it

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52
Q

why is water a good solvent?

A

because it is polar, anything that is polar or a charged ion can dissolve in it

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53
Q

why is water being a good solvent important for living organisms?

A

it means that various molecules and ions can dissolve in the blood plasma and be transported around the body to cells that need them

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54
Q

how does a substance dissolve in water?

A

the slightly positive end of a water molecule will be attracted to the negative ion and the slightly negative ends of the water molecule will be attracted to the positive ion meaning the ions will get totally surrounded by water molecules

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55
Q

why do water less dense when it is solid?

A

due to the polar nature. the water molecules in ice are held further apart because each water molecule forms 4 hydrogen bonds to other water molecules, making a spaced- out lattice, which is less dense and floats

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56
Q

why is it useful to living organisms when water is less dense when solid?

A

animals can stand and live on them

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57
Q

why is water cohesive?

A

stayed molecules are attracted to each other because of their polar nature (hydrogen bonds form)

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58
Q

why is cohesion of water useful?

A

helps water to flow as one mass making it useful to transport substances

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59
Q

what does adhesion in plants happen between?

A

the cellulose xylem wall and the water molecules due to the hydrogen bonds

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60
Q

why can water cause surface tension?

A

water molecules on surface are hydrogen bonded to the water molecules underneath and more attracted to the air molecules above, meaning the surface of the water contracts giving it the ability to resist force

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61
Q

why do surface tension important in living organisms?

A

allows little animals to walk on water and creates a habitat

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62
Q

what is specific heat capacity?

A

the energy needed to raise the temperature of 1kg of a substance by 1 degree

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63
Q

why does water have a high specific heat?

A

the hydrogen bonds between water molecules can absorb a lot of energy, so it takes up a lot of energy to heat up

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64
Q

why is a high specific heat capacity for water important?

A

water donkey experience rapid temperature changes, making it very stable therefore a good habitat for organisms and a good temperature for enzyme- controlled reactions inside cells

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65
Q

why does water have a high latent heat of evaporation?

A

it takes a lot of energy to break all if the hydrogen bonds between water molecules in order for it to turn from a liquid to a gas

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66
Q

how is the high latent heat of evaporation of water useful to living organisms?

A

use evaporation as a cooling mechanism. for example for sweat, heat is lost form the body to make the sweat evaporate from the surface of the skin

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67
Q

how do furry animals cool down by latent heat of evaporation when they don’t sweat?

A

cats have sweat glands on paws and saliva that evaporates. dogs pant and have paw pads. camels have fat in their humps to hydrate

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68
Q

what single monomer units are carbohydrates made from?

A

monosaccharides

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69
Q

when 2 monosaccharides join, what do they form?

A

a disaccharide

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70
Q

what is another name for monosaccharides and disaccharides?

A

simple sugars and complex sugars

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71
Q

what 2 monosaccharides make sucrose?

A

fructose and glucose

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72
Q

what 2 monosaccharides make maltose?

A

glucose and glucose

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73
Q

what 2 monosaccharides make lactose?

A

glucose and galactose

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74
Q

what is a polysaccharide?

A

when many polysaccharides join. they are not sugars as they have different properties

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75
Q

what are some examples of polysaccharides?

A

starch, glycogen and cellulose

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76
Q

what types of molecules are starch and glycogen?

A

energy storage molecules

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77
Q

what type of molecule is cellulose?

A

structural molecule

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78
Q

what type of molecule is a monosaccharide?

A

single molecule

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79
Q

how does a monosaccharide taste?

A

sweet

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80
Q

are monosaccharides soluble in water?

A

soluble

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81
Q

how many glycosidic bonds do monosaccharides have?

A

none

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82
Q

what is the structure of a monosaccharide?

A

exist as a single ring shape or as a straight chain

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83
Q

what is the role of a monosaccharide?

A

energy release, transported in blood, monomers for other carbohydrates

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84
Q

what are some examples of monosaccharides?

A

hexose (glucose, fructose, galactose), pentose (ribose, deoxyribose), trioses (glyceraldehyde)

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85
Q

what type of molecule is a disaccharide?

A

two molecules covalently bonded joined

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86
Q

how do disaccharides taste?

A

sweet

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87
Q

are disaccharides soluble?

A

yes

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88
Q

how many glycosidic bonds are there in a disaccharide?

A

a singular bond

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89
Q

what is the structure of a disaccharide?

A

two rings joined together

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90
Q

what is the role of a disaccharide?

A

energy release, storage and transport within plants

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91
Q

what are some examples of disaccharides?

A

sucrose, maltose and lactose

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92
Q

what type of molecule is a polysaccharides?

A

many molecules covalently joined to each other

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93
Q

how do polysaccharides taste?

A

not sweet

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94
Q

are polysaccharides soluble?

A

no

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95
Q

how many glycosidic bonds are there in polysaccharides?

A

many bonds

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96
Q

what is the structure of a polysaccharide?

A

kind chains with may be branched and coiled, making them compact

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97
Q

what are the roles of polysaccharides?

A

energy store and a structural component in cell walls

98
Q

what are some examples of polysaccharides?

A

starch, glycogen and cellulose

99
Q

what is the role of glucose in living ?

A

substrate used in aerobic respiration inside cells to release energy

100
Q

what are some characteristics that glucose has that makes it useful?

A

small meaning it can pass through easily, soluble, reactive, easily broken down

101
Q

what 2 forms does glucose exist in?

A

alpha and beta

102
Q

what does isomers mean?

A

same molecular formula but different structure

103
Q

how are alpha and beta glucose different?

A

alpha glucose has hydrogen on the top of carbon one and hydroxide on the bottom while beta has it opposite

104
Q

is glucose a triose, pentose or hexose?

A

hexose

105
Q

are ribose and deoxyribose triose, pentose or hexose?

A

pentose

106
Q

what is the difference between ribose and deoxyribose?

A

at carbon two, ribose has a hydrogen on top and a hydroxide on the bottom whereas in deoxyribose it is the opposite

107
Q

what is ribose used for?

A

rna nucleotides

108
Q

what is deoxyribose used for?

A

dna nucleotides

109
Q

what reaction occurs for disaccharides to form and how?

A

condensation reaction, forming a a 1-2 glycosidic bond

110
Q

why is the glycosidic bond called a 1-4 bond?

A

carbon number one on one of the glucose molecules and carbon number 4 on the other glucose molecule are bonded

111
Q

what reaction is used to break up a disaccharide and how?

A

a hydrolysis reaction by using heat or acid

112
Q

what role do sucrose and lactose have in organisms?

A

they can easily be hydrolysed bacl into monosaccharides for cellular respiration, sucrose is the main transport sugar in plants and lactose is found in mammalian milk so it has high energy content

113
Q

what type of glucose is starch made from?

A

alpha glucose

114
Q

what are the 2 different types of starch?

A

amylose and amylopectin

115
Q

what is the structure of amylose?

A

long chains of 1-4 linked alpha glucose, coiled into a spiral shape, stabilised by hydrogen bonds

116
Q

what is the structure of amylopectin?

A

long chains of 1-4 linked alpha glucose molecules with short side branches (1-6 linked)

117
Q

why is starch a great storage molecule?

A

the chain coils in a spiral shape, making it very compact. it is not soluble in water meaning it doesn’t affect the water potential of the cell

118
Q

what is the structure of glycogen?

A

long chains of alpha glucose with 1-4 glycosidic bonds and highly branched (branches have 1-6 glycosidic bonds)

119
Q

why is glycogen a good storage molecule?

A

it is highly branched with shorter chains making it extremely compact

120
Q

why would animal cells need an energy storage molecule that is even more branched than in plant cells?

A

allows rapid hydrolysis to provide high levels of glucose quicker

121
Q

is glycogen a storage molecule in plant or animal cells?

A

animal

122
Q

is starch a storage molecule in plant or animal cells?

A

plant

123
Q

what type of glucose in cellulose made from?

A

beta glucose

124
Q

what is the problem with joining beta glucose molecules?

A

the hydroxyl groups on carbon one and carbon four are too far apart to react

125
Q

how can beta molecule join together?

A

if every other molecule is “flipped 180” (alternate glucose flip upside down)

126
Q

what is the structure of cellulose?

A

the alternate glucoses are flipped, meaning it is a straight chain molecule rather than coiled. many chain are linked by hydrogen bonds forming microfibrils

127
Q

how does the structure of cellulose make it ideal for the structure of plant cell walls?

A

microfibrils have high tensile strength due to the glycosidic bonds and the hydrogen bonds. the macrofibrils are embedded in gel-like pectin to give more strength

128
Q

why is cellulose in the cell wall important?

A

helps cell remain turgid to prevent wilting

129
Q

what are fats at room temperature?

A

solid

130
Q

what are oils at room temperature?

A

liquid

131
Q

how do the elements in lipids differ from carbohydrates?

A

there is a less proportion oxygen

132
Q

are lipids polar or non-polar?

A

non-polar

133
Q

true or false? lipids are hydrophobic

A

true

134
Q

what is the structure of a triglyceride?

A

one glycerol molecule and 3 fatty acids

135
Q

what is glycerol?

A

a very simple alcohol

136
Q

what is a fatty acid?

A

long hydrocarbon chains with an acid group/carboxyl group (cooh) at one end

137
Q

how does a triglyceride form?

A

the oh on the fatty acids are lined up next to the oh groups on the glycerol. three condensation reactions occur

138
Q

what bonds form between a fatty acid and the glycerol in a triglyceride?

A

ester bond

139
Q

how would you break down a triglyceride?

A

need 3 water molecules and an enzyme to bring a hydrolysis reaction

140
Q

what is the structure of a saturated fatty acid?

A

no double bonds between carbon atoms

141
Q

what is the structure of a mono-unsaturated fatty acid?

A

one double bond between carbon atoms

142
Q

what is the structure of a polyunsaturated fatty acid?

A

more than one double bond between carbon atoms meaning multiple kinks and bends

143
Q

why are lipids not polymers?

A

a polymer is made up of a lot of similar monomer joined together while is made up of different things (a glycerol and 3 fatty acids)

144
Q

how are lipids good for insulation in living organisms?

A

they are poor conductors therefore they prevent heat loss. stored under skin

145
Q

how are lipids good for water proofing in living organisms?

A

hydrophobic because they aren’t polar. on the surface of leaves and feathers

146
Q

how are lipids good for protecting organs in living organisms?

A

they go around vital organs to prevent damage

147
Q

how are lipids good for acting as steroid hormones in living organisms?

A

cholesteral is used to make them. important role as chemical messengers in the body

148
Q

how are lipids good at being energy stores in living organisms?

A

long hydrocarbon chains contain a lot of energy. they are unreactive, insolube and compact

149
Q

how are lipids good energy sources in living organisms?

A

easily hydrolysed. fatty acids and glycerol can be respired and they release twice as much energy as carbohydrates

150
Q

how are lipids good for membrane structure in living organisms?

A

phospholipids make up the bilayer due to the hydrophilic phosphate heads and the hydrophobic fatty acid tails

151
Q

what are phospholipids?

A

modified triglycerides containing phosphorus

152
Q

is the phosphate head hydrophobic or hydrophilic and polar or non-polar?

A

hydrophilic and polar

153
Q

is the fatty acid tail hydrophobic or hydrophilic and polar or non-polar?

A

hydrophobic and non-polar

154
Q

why do phospholipids arrange in a bilayer?

A

the phosphate heads are attracted to the water (both inside and outside the cell) and the tails are repelled, leading to a hydrophobic core

155
Q

what are sterols?

A

very different lipid structure, based on complex alcohol molecules

156
Q

why do we think cholesterol is bad for us?

A

too much ldl in the blood can cause deposits in the walls of the coronary arteries and other arteries, narrowing arteries and restricting blood flow causing possible heart attacks

157
Q

what is the role of cholesterol in the membrane?

A

maintaining the social integrity and regulating the fluidity of the cell surface membrane

158
Q

what steroid hormones does cholesterol make in the body?

A

testosterone, androgens, cortisol, progesterone and oestrogen

159
Q

what monomers make proteins?

A

amino acids

160
Q

how many different amino acids are there?

A

20

161
Q

how do amino acids differ from each other?

A

they each have different r-groups

162
Q

what type of reaction joins amino acids together?

A

condensation reaction

163
Q

what is a diptide?

A

when 2 amino acids join together

164
Q

what is a polypeptide?

A

when many amino acids are joined together

165
Q

what enzyme is involved in joining amino acids together?

A

peptidyl transferases

166
Q

when in the cell are proteins made?

A

ribosomes

167
Q

how is a diptide broken down?

A

hydrolysis reaction

168
Q

how can you turn a polypeptide chain into functional proteins?

A

by folding and twisting into different shapes

169
Q

what are the different levels of proteins?

A

primary, secondary, tertiary and quaternary

170
Q

what is the primary structure of a protein?

A

determines how the protein twists and folds into its final shape

171
Q

what bond is present in the primary structure of a protein?

A

peptide bonds

172
Q

how do hydrogen bonds form in the secondary structure of proteins?

A

hydrogen, oxygen and nitrogen (not the r-groups) interact

173
Q

what do the hydrogen bonds do in the secondary structure of proteins?

A

form at various points along the chain, pulling it into regularly arranged shapes

174
Q

what are the 2 shapes of the secondary structure of proteins?

A

alpha helix \and beta pleated sheet

175
Q

how many polypeptides are secondary structure of protein made from?

A

one

176
Q

how many polypeptides are tertiary structure of protein made from?

A

one

177
Q

how is the polypeptide in tertiary structure proteins made into various shapes?

A

the r-groups of different amino acids interact with each other when they are close enough and are pulled into a specific 3d shape

178
Q

what 4 interactions can take place in the making of a tertiary structure of a protein?

A

hydrophilic/hydrophobic interactions, hydrogen bonds, ionic bonds and disuphide bonds/bridges

179
Q

how many polypeptides are the quaternary structure of proteins made from?

A

more than one

180
Q

what bonds hold tertiary and quaternary structures of proteins in place?

A

hydrogen, ionic and disiphide

181
Q

what are some examples of proteins in the quaternary structure?

A

enzymes, hormones, hemoglobin and collagen

182
Q

what are the characteristics of globular proteins?

A

compact, water soluble , roughly spherical shape, easily transported and usually have metabolic roles

183
Q

out of the 4 structures of proteins, which ones form globular proteins?

A

tertiary and quaternary

184
Q

how do globular proteins arrange themselves (hydrophobic and hydrophilic)?

A

amino acids with the hydrophobic r-groups position themselves towards the centre of the protein, amino acids with the hydrophilic r-groups position themselves around the edges of the protein

185
Q

what are 3 globular proteins?

A

haemoglobin, insulin and amylase

186
Q

how many polypeptide chains is haemoglobin made from?

A

4

187
Q

what is the job of haemoglobin?

A

carries oxygen around the body in red blood cells

188
Q

why is haemoglobin known as a conjugated protein?

A

it’s a protein wit a non-protein group attached called the prosthetic group

189
Q

what is the haem group made from in haemoglobin?

A

iron

190
Q

how many polypeptide chains is insulin made from?

A

2

191
Q

what is the role of insulin?

A

helps regulate blood glucose levels

192
Q

what does insulin structurally do in the pancreas?

A

6 of the molecules bind together to form a large, globular structure

193
Q

how many polypeptide chains is amylase made from?

A

one which is twisted and folded

194
Q

what is amylase?

A

an enzyme that catalyses the breakdown of starch in the digestive system

195
Q

what is amylase made from?

A

alpha helix and beta pleated sheets

196
Q

what are the characteristics of fibrous proteins?

A

long and thin strands, insoluble, small r-groups, not folded into 3d shapes, strong and metabolically inactive

197
Q

why do fibrous proteins have their characteristics?

A

they contain a limited range of amino acids and have a repetitive primary sequence. they tend to contain a lot of amino acids which have small hydrophobic r-groups

198
Q

what are 3 examples of fibrous proteins?

A

keratin, elastin and collagen

199
Q

what is the structure of keratin?

A

2 parallel alpha helices twisted around each other

200
Q

what are the characteristics of keratin?

A

strong and fairly flexible

201
Q

what is keratin used for?

A

in hair and nails

202
Q

how is keratin flexible?

A

has a large proportion of sulfur-containing amino acids, meaning strong disulfide bonds. the degree of disulfide bonds determines flexibility. fewer bonds = more flexible

203
Q

what is elastin made from?

A

many stretchy protein fibres called tropoelastin which have the ability to stretch and coil

204
Q

what is elastin used for?

A

in the walls of blood vessels and surrounding the alveoli in the lungs

205
Q

what is the structure of collagens?

A

3 polypeptides wound together in a long and strong rope-like structure

206
Q

what is collagen used for?

A

as a connective tissue in skin, tendons, ligaments and the nervous system

207
Q

what level of protein structure do keratin/elastin/collagen all show?

A

quaternary because they have more than one polypeptide chain

208
Q

what is the sequence of amino acids in fibrous proteins?

A

repetitive amino acid sequence

209
Q

what is the sequence of amino acids in globular proteins?

A

irregular amino acid sequence

210
Q

how stable are fibrous proteins?

A

less sensitive to changes in heat and ph

211
Q

how stable are globular proteins?

A

more sensitive to changes in heat and ph

212
Q

how can computers model protein structure?

A

can predict the structure of proteins based on the amino acid sequence (primary structure)

213
Q

how is computer modelling of proteins structure useful?

A

protein structures can be used in medicine like in the production of synthetic antibodies, enzymes and hormones

214
Q

what are the 2 approaches to computer modelling for protein structure?

A

ab initio protein modelling and comparative protein modelling/protein threading

215
Q

what happens during ab initio protein modelling?

A

interprets physical and electrical properties of atoms in each amino acid present. then predicts the outcome in terms of secondary and tertiary structure of final protein. there may be many outcomes

216
Q

what happens during comparative protein modelling/protein threading?

A

scans amino acid sequences against a data base and produces models of what the final structure might be. the may be many outcomes

217
Q

what is the test for starch?

A

iodine test

218
Q

what is the method of the iodine test?

A

add 1cm of sample to each dimple of a spotting tile and add a few drops of iodine solution to each

219
Q

what is the positive result of the iodine test?

A

orange > black/blue

220
Q

what is the test for lipids?

A

emulsion test

221
Q

what is the method for the emulsion test?

A

add 1cm of ethanol to a test tube and add 1cm of the sample. shake vigorously to dissolve and add 1cm of cold water

222
Q

what is a positive result for the emulsion test?

A

clear > cloudy emulsion

223
Q

what is the test for proteins?

A

biuret test

224
Q

what is the method for the biuret test?

A

add 2cm sample solution to a test tube and add 2cm of biuret solution

225
Q

what is the positive result of the biuret test?

A

blue > purple/lilac

226
Q

what is the test for reducing sugars?

A

benedict’s test

227
Q

what is the method for the benedict’s test?

A

add 2cm of sample solution to a test tube and add 2cm of benedicts solution. heat gently in a water bath at 85 degrees for 2 minutes

228
Q

what is the positive result of the benedict’s test?

A

blue > green/red/brick red

229
Q

how do you test for non-reducing sugars?

A

add 2cm of sample solution to a test tube and add 1cm of 1m hydrochloric acid then boil in a water bath for one minute. carefully neutralise with sodium bicarbonate. to make sure, check the ph with indicator paper and then carry out the benedict’s test

230
Q

what is the positive test for non-reducing sugars?

A

blue > green/red/brick-red

231
Q

what is chromatography?

A

allows the separation of components from a mixture of molecules

232
Q

what are the 2 types of chromatography?

A

paper and thin layer chromatography

233
Q

what is the mobile phase in chromatography?

A

where the molecules can move

234
Q

what is the mobile phase in paper and thin layer chromatography?

A

a liquid solvent

235
Q

what is the stationary phase?

A

where molecules can’t move

236
Q

what is the stationary phase of paper and thin layer chromatography?

A

paper - piece of paper and thin layer - layer of solid

237
Q

what 2 factors does the process of chromatography depend on?

A

capillary action and solubility

238
Q

what is capillary action in chromatography?

A

movement of liquid within spaces of a porous material due to adhesion, cohesion and surface tension

239
Q

what is solubility in chromatography?

A

the degree to which the solute dissolves into the solvent which allows different solutes to be separated by different combinations of solvents

240
Q

what is the method for paper chromatography?

A

draw a pencil line 1.5cm up from the bottom of the paper and place the first dot of the sample on this line and repeat until all the samples are there. put the paper into the solvent ensuring the solutes aren’t in the solvent. whe the solvent reaches the top of the paper, mark with a pencil (solvent front) and let the paper dry

241
Q

how do you calculate the rf values?

A

distance travelled by solvent

biology (10 decks)

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