Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Biological Molecules > Flashcards

Biological Molecules Flashcards

BIOCHEM IS FUN WHEYYYYY

1
Q

What are the 4 organic molecules?

A

Carbohydrates, Lipids, Proteins, Nucleic acids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What nucleic acids do all organisms use?

A

The same ones as each other.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many amino acids are there?

A

20.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What molecules do all organisms use for energy?

A

Carbohydrates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do all organisms use for cell membranes?

A

Lipids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What thory does the biological similarities between organisms support?

A

Theory that all animals and plants share a commono ancestor.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are monomers?

A

The smaller units that can join together to make larger molecules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are polymers?

A

Molecules made from lots of repeating unts joined together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Give 3 examples of monomers.

A

Monosaccharides, amino acids and nucleotides.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens in condensation?

A

Two monomers join together and form a covalent bond with the elimination of water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens in hydrolysis?

A

Addition of a water molecule is used to break apart the covalent bond between monomers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a monosaccharide?

A

Monomer of a carbohydrate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are 3 examples of monosaccharides?

A

Glucose, fructose, galactose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the differences between hexose and pentose sugars?

A

Hexose sugars have 6 carbons and pentose sugars have 5 carbons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

MAKE PAPER CARDS FOR DIAGRAM OF ALPHA AND BETA GLUCOSE.

A

please remove when done

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Is glucose a hexose or pentose sugar?

A

Hexose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is an isomer?

A

Molecules with the same forumla but have different structures.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 2 isomers of glucose?

A

alpha and beta.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How are glucose’s isomers different.

A

The hydrogen and hydroxide on carbon 1 are the other way around.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How are carbons numbered in diagrams of glucose?

A

Clockwise, with carbon 1 being first after the oxygen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How do monosaccharides bond together?

A

Condensation reactions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What type of bond forms from condensation of monosaccharides?

A

A glycosidic bond.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

DRAW OUT GLYCOSIDIC BOND CARD

A

please remove when done.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are disaccharides?

A

Two monosaccharides bonded together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Give 3 examples of disaccharides.

A

Maltose, Sucrose, Lactose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What monosaccharides make maltose?

A

Glucose-glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What monosaccharides make sucrose?

A

Glucose-fructose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What monosaccharides make lactose?

A

Glucose-galactose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What can reducing sugars do?

A

Donate electrons to other compounds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Give 5 examples of reducing sugars.

A

Glucose, fructose, galactose, maltose, lactose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Give an example of a non-reducing sugar.

A

Sucrose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are polysaccharides?

A

Polymer carbohydrates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are polysaccharides made of?

A

Lots of monosaccharides bonded together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Give 3 examples of polysaccharides.

A

Glycogen, cellulose, starch.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is starch made of?

A

Alpha glucose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the diference between 1-4 and 1-6 glycosidic bonds?

A

The carbons that are joining together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

DRAW ALPHA 1-4, ALPHA 1-6, AND BETA 1-4 GLYCOSIDIC BONDING

A

please remove when done.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What 2 polysaccharides is starch made up of?

A

Amylose and amylopectin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Describe the shape of amylose.

A

A long unbranched chain that forms a coiled helical shape.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What type of bonds does amylose contain?

A

Alpha 1-4 glycosidic bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is amylose used for?

A

Storing excess glucose to convert back for energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

How does the structure of amylose help with its function?

A

Helical shape allow it to be compact so lots can be stored in a small space.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Describe the structure of amylopectin.

A

A long branched chain of alpha glucose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is amylopectin used for?

A

Storing excess glucose that can be used later.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

How does the structure of amylopectin aid its function?

A

Branches increase the surface area so it can be hydrolised for glucose easily.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

How do the properites of starch aid their function? (2)

A

It is too large to leave cells so will always be readily available.
It is insoluble so cannot affect water potential and osmosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What type of bonds does amylopectin contain?

A

Alpha 1-4 and alpha 1-6 glycosidic bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is glycogen made out of?

A

Alpha-glucose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Describe the structure of glycogen.

A

Long branched polysaccharide.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

How does the structure of glucose compare to amylopectin?

A

Glucose has many more branches.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What type of bonds does glycogen contain?

A

Alpha 1-4 and alpha 1-6 glycosidic bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Where is glycogen found?

A

In animal cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is glycogen used for?

A

Storing excess glucose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Where in the body is glycogen usually found in cells?

A

Muscles and the liver.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

How does the structure of glycogen aid its function? (2)

A

The branches increase the surface area so it can be hydrolysed more easily.
It is a compact molecule so is good for storage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Where is cellulose found?

A

In plant cell walls.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is cellulose made of?

A

Beta-glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What bonds make up glucose?

A

Beta 1-4 glycosidic bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

How are the glucose molecules oriented in cellulose? (why?)

A

Alternating molecules are inverted so the -OH groups are lined up to form bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Describe the general structire of cellulose.

A

Long unbranched chains held together by hydrogoen bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What do the cellulose chain form when joined by hydrogen bonds?

A

Fibres called microfibrils.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What is cellulose used for?

A

Providing structure in cell walls, allowing the wall to stay rigid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

How do the properties of cellulose help with its function?

A

Hydrogen bonds make microfibrils very strong but also flexible.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Where are 1-6 glycosidic bonds found?

A

At points where polysaccharide chains are branched.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

How are lipids different from carbohydrates and proteins?

A

Lipids are NOT polymers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What are the main functions of lipids? (4)

A

Waterproofing, insulation, protection/membranes, and emergency energy supplies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What is a triglyceride made up of?

A

A glycerol molecule and three fatty acid chains.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What can triglycerides be used for?

A

An energy store, as lots of energy can be released as chains are broken down.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What bonds do lipids form during condensation?

A

Ester bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What do ester bonds form between?

A

Between -OH groups on fatty acid chains and on the glycerol molecule.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

DRAW STRUCTURE OF A TRIGLYCERIDE CARD

A

please deletw when finished

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

DRAW ESTER BOND CARD

A

please delete when finished.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What property can the fatty acid HYDROCARBON chain have in triglycerides?

A

They can be saturated or unsaturated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Define saturated.

A

Only single bonds between the carbons in the chain, so the maximum number of hydrogens can bond to each carbon atom.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Define monounsaturated.

A

There is only one c=c double bond between carbons in the chain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

Define polyunsaturated.

A

More than one c=c double bonds between carbons within the chain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Why are lipids insoluble in water?

A

They are not polar (do not have a charge)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

How do phospholipids react in water?

A

They bundle together as insoluble droplets with the glycerol heads shield the tails from the water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What are phospholipids made up of?

A

A glycerol molecule, a phosphate group, and two fatty acid chains.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

How does the structure of a phospholipid differ from a triglyceride?

A

In phospholipids, one of the fatty acid chains is replaced by a phosphate group.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What can phospholipids be used for?

A

Membranes and hormones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

How do the different parts of a phospholipid behave near water?

A

The head is hydrophilic and the 2 tails are hydrophobic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What is different about the specific structures of the fatty acid chains in phospholipids?

A

There is always one saturated and one unsaturated chain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What feature do unsaturated fatty acid chains have? (why?)

A

The c=c double bond causes the chain to bend and create a kink, as the lack of hydrogens in the way allows the carbons to move closer together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

How do the properties of phospholipids aid its function?

A

Thy hydrophobic tails and hydrophilic head allow phospholipids to form bilayers for membranes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

DRAW BILAYER MEMBRANE

A

remove when done please.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Why can water soluble substances not easily pass through a phospholipid bilayer?

A

The centre of the bilayer is hydrophobic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

What is the monomer for proteins?

A

Amino acids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

How many amino acids are there?

A

20.

90
Q

What do all amino acids share?

A

A basic structure.

91
Q

DRAW AMINO ACID BASIC STRUCTURE

A

please remove when done

92
Q

What is the variable part of a molecule called?

A

R-group

93
Q

What is the R-group of molecules?

A

The part of the molecule that may vary between different molecules.

94
Q

What is the R-group of glycine?

A

Just a hydrogen.

95
Q

What can the R-group contain other than C,O,H?

A

Other elements (cytesine has sulfur).

96
Q

How do amino acids join?

A

Condensation reactions.

97
Q

What bond forms between amino acids?

A

Peptide bonds.

98
Q

Where does the peptide bond form between amino acids?

A

Between the amine group of one and the carboxyl group of another amino acid.

99
Q

DRAW FORMATION OF A PEPTIDE BOND.

A

please remove when gone.

100
Q

What is made when 2 amino acids are joined?

A

Dipeptide.

101
Q

What is the amine group?

A

-H2N

102
Q

What is the carboxyl groups?

A

-COOH

103
Q

How are dipeptides and polypeptides broken down?

A

Hydrolysis.

104
Q

What is a hydroxyl group?

A

-OH

105
Q

How many levels of protein structure are there?

A

4.

106
Q

How do proteins form? (get to each stricture)

A

The polypeptides fold.

107
Q

What is the primary structure of proteins?

A

Simple polypeptide chains.

108
Q

Can a primary structure protein function?

A

NOPE AND THATS A BIT OF AN L.

109
Q

What is important about the structure of primary proteins?

A

The number and sequence of the amino acids determines the tertiary structure.

110
Q

What about enzymes can the the order and number of amino acids in a polypeptide affect?

A

The shape of the active site.

111
Q

What is the secondary structure of proteins?

A

Alpha-helix or beta-pleated sheet.

112
Q

Why do polypeptides start to fold into the secondary structure?

A

Hydrogen bonds forming between the amino acids.

113
Q

What does hydrogen bonds forming between amino acids cause?

A

Folding into an alpha-helix or a beta-pleated sheet.

114
Q

Why is the secondary structure of proteins stable?

A

The hydrogen bonds keep the structure stable.

115
Q

What is a use of alpha-helices?

A

Channel proteins in membranes.

116
Q

What is the structure of teriary proteins?

A

The fully formed shape of the 3D polypeptide chain.

117
Q

What is a tertiary protein? (description)

A

A complex folded 3D shape made of a polypeptide chain.

118
Q

Why do tertiary proteins have a very specific shape?

A

Thw sequence of amino acids determines which R-groups begin to form bonds.

119
Q

What types of bond can form between the R-groups of tertiary proteins? (3)

A

Hydrogen bonds, ionic bonds, disulphide bridges (covalent).

120
Q

Give 3 examples of tertiary proteins.

A

ALL enzymes, ALL anitibodies, SOME hormones.

121
Q

WHO’S THE MOST SIGMA

A

GRACE OFC

122
Q

What are quaternary proteins made of?

A

Multiple polypeptide chains.

123
Q

Give an example of a quaternary protein

A

Haemoglobin.

124
Q

What is a prosthetic group?

A

A non-protein group that is part of a quaternary protein.

125
Q

What is the prosthetic group in haemoglobin, and what does it contain?

A

The haem group that contains iron.

126
Q

What is a glycoprotein?

A

A protein that also contains a carbohydrate group.

127
Q

What is a lipoprotein?

A

A protein that also contains a lipid group.

128
Q

What is the function of enzymes?

A

Speed up rates of reaction.

129
Q

What are enzymes?

A

Biological catalysts.

130
Q

How do enzymes achieve their function?

A

By lowering activation energy.

131
Q

What is a catalyst?

A

A substance that can speed up a chemical reaction without getting used up in the process.

132
Q

What reactions can a single enzyme catalyse? (how broad)

A

Enzymes catalyse a specific ?, typically only one.

133
Q

What is a catabolic reaction?

A

A reaction that breakes a substrate down.

134
Q

What is an anabolic reaction?

A

A reaction that joins substrates together.

135
Q

What type of structure do enzymes have?

A

3D tertiary protein structure.

136
Q

What sort of shape is an enzyme’s active site?

A

Specific.

137
Q

What type of substrates can a certain enzyme bind to?

A

Certian substrates only.

138
Q

What is formed when an enzyme and a substrate bind?

A

An enzyme-substrate complex (E-S complex).

139
Q

What is an enzyme-substrate complex?

A

A substance formed of an enzyme that has bound to a substrate.

140
Q

How can you describe an enzyme’s active site when compared to the substrate?

A

The shapes are complimentary.

141
Q

Define complimentary.

A

The way that 2 shapes fit together (enzymes)

142
Q

What does a lower activation energy allow in reactions?

A

The reaction can take place at a lower temperature.

143
Q

How do enzymes lower activation energy? (2)

A

Holding substrates together so there is less repultion and they can bond more easily.
Putting more strain on the bonds of a substrate so it can break apart.

144
Q

What is the lock and key model?

A

The enzyme active site is exactly complimentary to the shape of the substrate so they fit together perfectly (hence enzymes are specific).

145
Q

What is the induced fit model?

A

The active site can change slightly to fit the substrate when they collide and form an e-s complex.

146
Q

What made the induced fit model more plausible?

A

Enzymes being able to catalyse multiple substrates.

147
Q

DRAW LOCK AND KEY MODEL

A

please remove when done

148
Q

What factors are able to affect enzyme action? (4)

A

Enzyme concentration, substrate concentration, temperature, pH

149
Q

DRAW GRAPH FOR EACH FACTOR, USE BOOKLET

A

please remove when done

150
Q

How does enzyme concentration affect rate of reaction?

A

There are more enzymes that are available to form E-S complexes so the rate will increase.

151
Q

Why does a graph of enzyme concentration plateau?

A

The substrate becomes the limiting factor so increasing number of enzymes will not affect the rate.

152
Q

How does substrate concentration affect rate?

A

It will initially increase as there are more collisions occuring, but then it will slow as enzymes become a limiting factor. As all active sites are occupied (saturation point) increasing the substrate will have less effect.

153
Q

What is the saturation point (enzymes)?

A

Where all the enzyme active sites are occupied.

154
Q

How does temperature affect enzyme concentration?

A

There is more kinetic energy so molecules move faster and there are more successful collisions. Rate will increase up to the point where it is too hot and bonds eithing the enzymes break, causing the tertiary structure to change so no more substrates can react (active site is different). The enzyme is permanently denatured.

155
Q

What does denatured mean?

A

When the enzyme permanently changes shape as the bonds in the tertiary structure have broken.

156
Q

How does pH affect enzyme function?

A

Above and below the optimum pH the concentrations of H+ and OH- ions disrupt ionic and hydrogen bonds, causing the enzyme to denature.

157
Q

How do inhibitors prevent enzyme function?

A

They stop substrates from binding.

158
Q

What is an inhibitor?

A

A substance that prevents enzyme function by stopping substrates from binding.

159
Q

What are the 2 types of inhibitor?

A

Competitive and non-competitive.

160
Q

How are competitive inhibitors similar to substrate molecules?

A

They both have a similar shape.

161
Q

How do competitive inhibitors prevent enzyme function?

A

They compete with substrates to block the active site, so substrates cannot bind anymore.

162
Q

How can competitive inhibitors be challenged?

A

Increasing the substrate concentration will increase the rate of reaction still as the substrates out-compete the inhibitor for enzyme active sites.

163
Q

Where do non-competitive inhobitors bind?

A

The allosteric site of the enzyme.

164
Q

How do non-comopetitive inhibitors affect enzyme function?

A

By binding to the allosteric site they change the shape of the active site so it is no longer complimentary to the substrate.

165
Q

Can you out-compete a non-competitive inhibitor?

A

No. as the substrates can no longer bind anyway.

166
Q

DRAW COMP AND NON COMP INHIBITOR FUNCTION

A

please remove when done.

167
Q

What is the reducing sugars test used to find? (examples)

A

All monosaccharides, some disaccharides like maltose and lactose.

168
Q

What is the reagent for the reducing sugars test?

A

Benedict’s reagent.

169
Q

What colour is benedict’s reagent at the start of the test?

A

Pale blue.

170
Q

What are hazards for the reducing sugars test? (2)

A

Benedict’s reagent is an irritant.
Hot water can cause burns.

171
Q

What are precautions taken for the reducing sugars test? (2)

A

Wear goggles, wash hands on contact (benedict’s).
Use caution when pouring or carrying (hot water).

172
Q

What is the method for the reducing sugars test?

A

Add excess benedict’s to the sample, heat in boiling water bath (>80 degrees)

173
Q

What is a positive result for the reducing sugars test?

A

A precipitate (colour from yellow to brick red based on amount of sugar) will form.

174
Q

What is a negative result for the reducing sugars test?

A

The solution will remain blue.

175
Q

What is the non-reducing sugars test to find? (examples)

A

Disaccharides or polysaccharides like sucrose.

176
Q

When is the non-reducing sugars test used?

A

If a negative result is taken from the reducing sugars test.

177
Q

How does the non reducing sugars test vary from the reducing sugars test?

A

Add dilute HCl and heat to break bonds FIRST.
Then add an alkali (NaOH) to neutralise
Continue as for reducing sugars.

178
Q

How can results from sugar tests be made quantitative? (2)

A

Filter and weigh the precipitate.
Remove precipitate and use a colourimeter.

179
Q

How do you test for starch?

A

Add iodine.

180
Q

What hazards and precautions are taken when testing for starch?

A

Iodine is an irritant so wear goggles and wash hands if comes into contact.

181
Q

What are the possible results for a starch test?

A

Positive: goes blue/black
Negative: stays brown/yellow.

182
Q

What type of data is a result from a starch test?

A

Qualitative only (it is yes/no)

183
Q

What is the protein test for? (examples)

A

Presence of amino acids.

184
Q

What is the reagent in the protein test?

A

Biuret reagent.

185
Q

What colour is biuret reagent?

A

Pale blue (dilute CuSO4 and NaOH)

186
Q

What hazards and precautions are found for the protein test?

A

Biuret is an irritant: goggles are worn, hands washed when in contact.

187
Q

What is the method for the protein test?

A

Add excess biruet and shake.

188
Q

What are the results for the protein test?

A

Positive: goes purple
Negative: stays blue.

189
Q

How could you make a protein test quantitative?

A

Chromatography can be used to identify certian amino acids in a mixture by separating them by mass.

190
Q

Why is the protein test qualitative?

A

A stronger purple means more amino acids are present.

191
Q

What is the lipids test for?

A

Lipids you fool what else would it be for >:)

192
Q

What is the reagent for a lipids test?

A

Emulsion test using ethanol and water.

193
Q

What precautions and hazards can be found for the emulsion test?

A

Ethanol is flammable: do not do the test near a naked flame.

194
Q

What is the method for the emulsion test?

A

Add ethanol (to emulsify), THEN water.

195
Q

What are the results for the emulsion test?

A

Positive: a MILKY WHITE EMULSION forms on the top
Negative: nothingi happens.

196
Q

Why is the emulsion test qualitative?

A

The more lipids are present the more opaque the emulsion will be, it is qualitiative only.

197
Q

How can water be described? (importance)

A

Biologically important.

198
Q

Is water a monomer or a polymer?

A

NO

199
Q

What are the 2 types of bonding between molecules?

A

Ionic and covalent (chem flashbacks ewwww)

200
Q

What is ionic bonding between?

A

Metals and non-metals.

201
Q

How does ionic bonding work?

A

Metal donates electron to non metal.

202
Q

What charges are gained in ionic bonding?

A

Metal becomes positive, non metal becomes negative.

203
Q

What is covalent bonding between?

A

Non-metals only.

204
Q

What happens in covalent bonding?

A

Atoms share electrons.

205
Q

What is electronegativity?

A

Where some atoms attract electrons better than others.

206
Q

Why does electronegativity happen?

A

Bigger nucleus means more protons to attract electrons with.

207
Q

Is water more electronegative, or hydrogen?

A

WATERRRR

208
Q

What is a polar molecule?

A

Molecule with a slight uneven distribution of charge.

209
Q

How is water a polar molecule?

A

Electrons are pulled to the oxygen (becomes delta negative), while hydrogen becomes delta positive.

210
Q

How would you describe an atom with a very slight charge?

A

Delta positive/negative.

211
Q

What is hydrogen bonding? (in water)

A

Hydrogens get attracted slightly to the other oxygens.

212
Q

What are properties of hydrogen bonding? (single/multiple)

A

Weak on their own, strong when there are lots.

213
Q

What is cohesion?

A

When molecules attract each other.

214
Q

How can you tell that water is cohesive?

A

It forms droplets.

215
Q

How do the water molecules form up?

A

In a lattice structure.

216
Q

DRAW WATER LATTICE STRUCTURE

A

please remove when done.

217
Q

What is suface tension?

A

Intermolecular attraction at the surface of a liquid, agains a gas.

218
Q

What is adhesion?

A

Water’s tendency to stick to surfaces (inside of tubes)

219
Q

Give some properties of water? (9)

A
  • Wide temp range as a liquid
  • below 4 degrees is less dense than above
  • high shc (4200j/kg degree)
  • high latent heat of evaporation (100j/degree)
  • polar
  • is a reactant (photosynthesis/hydrolysis)
  • has many hydrogen bonds
  • transparent
  • is a solvent
220
Q

How do the properties of water aid its function? (6)

A
  • Lower density cold water allows ice to float and currents to occur in the sea
  • High SHC makes water a good buffer as there is no rapid temperature change.
  • High latent heat of vapourisation allows sweat to absorb heat
  • As it is a polar molecule it allows things to be dissolved into it.
  • The many hydrogen bonds lead to properties of cohesion, adhesion and surface tension.
  • As water is a solvent it allows for transpiration

Biology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions