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Biology > Topic 1: Biological Molecules > Flashcards

Topic 1: Biological Molecules Flashcards

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1
Q

What does common biochemistry indicate about evolution? Why?

A
  • Shows a common ancestry between living organisms

- All organisms derived from a common beginning

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2
Q

What is a polymer?

A

A long chain of monomers joined together

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3
Q

What is a monomer?

A

Small units from which large molecules (polymers) form

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4
Q

Starch is a polymer, what is it’s monomer?

A

Alpha Glucose

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5
Q

Glycogen is s polymer, what is it’s monomer?

A

Alpha Glucose

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6
Q

Cellulose is a polymer, what is it’s monomer?

A

Beta Glucose

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7
Q

Protein is a polymer, what is it’s monomer?

A

Amino Acids

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8
Q

What are the monomers of polysaccharides?

A

Monosaccharides; Glucose, Fructose and Galactose

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9
Q

What is covalent bonding?

A

Where atoms share electrons

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10
Q

What is ionic bonding?

A
  • Atoms with opposite charges are attracted to each other

- Weaker than covalent bonds

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11
Q

What is Hydrogen bonding?

A
  • Electrons are unevenly distributed causing slight differences in charges, a polar molecule
  • Individually weak, collectively strong
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12
Q

What is the name of a reaction where a water molecule is released?

A

A condensation reaction

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13
Q

What is the name of a reaction where a water molecule is added?

A

Hydrolysis

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14
Q

What is the molecular formula of Glucose?

A

C6 H12 O6

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15
Q

What is the general molecular formula for a monosaccharide?

A

Cn H2n On

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16
Q

What is the difference between alpha and beta glucose?

A
  • The hydrogen and hydroxide arms on the right hand side are the other way round.
  • a glucose has hydrogen at top and hydroxide on bottom at both ends.
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17
Q

What is an isomer? Can you name an example?

A
  • The same molecule but in a different arrangement/structure giving it different properties
  • eg Alpha/Beta glucose
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18
Q

What is the food test for reducing sugars? How do you do it?

A
  • Use benedict’s test (benedict’s reagent is blue)
  • Add 1cm^3 of solution to test tube, heat
  • Colour change from blue-red, depends on Concentration.
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19
Q

What is making a range of dilutions called?

A

A serial dilution

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20
Q

What type of reaction is it when two monosacchrides join together?

A

A condensation reaction

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21
Q

Maltose is a disacchride, what are it’s monosacchrides?

A

2 alpha glucose

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22
Q

Sucrose is a disacchride, what are it’s monosacchrides?

A

Alpha glucose and fructose

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23
Q

Lactose is a disacchride, what are it’s monosacchrides?

A

Alpha glucose and galactose

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24
Q

Name 3 disacchrides

A
  1. Maltose
  2. Lactose
  3. Sucrose
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25
Q

What type of bond is formed when two monosacchrides join to make a disacchride?

A

A glycosidic bond

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26
Q

What is the main use of disacchrides in living organisms?

A

In respiration (called respiratory molecules)

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27
Q

What is the role of Glycogen?

A

Energy storage in animals, specifically liver/muscles

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28
Q

What is the role of Starch?

A

Energy storage in plants (seeds)

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29
Q

What is the role of Cellulose?

A

Gives strength to plant cell walls

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30
Q

Starch is insoluble. Why is this important?

A
  • A storage molecule, being insoluble prevents excess water entering cells
  • No osmotic effect or effect on water potential
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31
Q

Why is it important for starch to have a compact structure?

A

It can fit a lot into a small space

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32
Q

What property of starch makes it suitable for enzymes to work on?

A

It has multiple branches from chains (carbon 1-6 glycosidic bonds

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33
Q

What is the test for presence of starch?

A
  • Use iodine in potassium iodide

- Colour change from red->blue->Black

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34
Q

What is the structural difference between Starch and glycogen?

A

Glycogen has more 1-6 branches

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35
Q

What must happen to beta glucose in order to create cellulose?

A

The individual beta glucose molecules need to be flipped round between every one. (flip-flop)

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36
Q

How to some herbivores (eg cows) manage to digest cellulose?

A
  • Cows have 4 stomachs

- 1 stomach contains a bacteria which produces celluase to digest the cellulose

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37
Q

Name 5 Key features of Cellulose structure

A
  1. B glucose linked by glycosidic bond 1:4 (flip/flop)
  2. Hydrogen bonds form cross links + microfibrils
  3. Provides strength to cells
  4. Resists turgor/osmotic pressure
  5. 1:4 bonds are difficult to break, resisting digestion
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38
Q

What are the 2 groups of lipids?

A

Triglyerides and phosopolipids

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39
Q

How are triglycerides formed?

A

The condensation reaction of one molecule of glycerol and three molecules of fatty acid

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40
Q

What is the general formula for a fatty acid?

A

HOOC - [CH2}n - CH3

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41
Q

What is the bond between a fatty acid and a glycerol called?

A

A ester bond

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42
Q

What is the functional group (at end of repeating hydrocarbon units) on a fatty acid called?

A

The carboxyl group

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43
Q

How does a saturated fat differ from an unsaturated fat?

A

Saturated fats have no double C=C bonds, unsaturated fats do

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44
Q

What is fat used for in biological organisms?

A
  • Water proofing (waxy cuticle)
  • Insulation
  • Protection
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45
Q

What is the difference between a phospholipid and a triglyceride?

A

Phospholipids have a phosphate group instead of one of the 3 fatty acids in triglycerides

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46
Q

What cellular structure contains phospholipids?

A

Cell membranes

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47
Q

Which part of a phospholipid molecule is hydrophilic?

A

The phosphate group (head)

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48
Q

Which part of a phospholipid molecule is hydrophobic?

A

The fatty acid tails

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49
Q

True or false: Phospholipids are polar molecules.

A

True

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50
Q

What does hydrophilic mean?

A

Attracted to water

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51
Q

How would you test for NON-reducing sugars?

A
  • Non reducing sugars are disacchrides
  • Add dilute HCl, boil
  • Neutralise with Sodium hydroxide
  • Use benedicts test
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52
Q

What are the two polysacchrides of starch?

A
  1. Amylose; Unbrached chain of a glucose, coiled, good for storage
  2. Amylopectin; Branched, allowing for enzymes to break it down and release stored glucose for energy
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53
Q

Are triglycerides soluable in water?

A

No. They are insoluble because the tails are hydrophobic

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54
Q

Why are unsaturated fatty acids better insulation for organisms in cold climates?

A

The C=C double bond causes a kink in the fatty acid chain, irregular shape interrupts conduction

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55
Q

Why are triglycerides good storage molecules?

A
  1. Long hydrocarbon tails stores chemical energy
  2. Insoluble, causing no effect on water potential, so the cell is unaffected by osmotic effect
  3. Low mass
  4. Source of water (through hydrolysis)
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56
Q

How do you test for lipids?

A
  • Use emulsion test
  • Add alcohol, shake
  • Add to water
  • Milky emulsion/layer will form
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57
Q

What is the term used to describe all chemical processes that take place in living organisms?

A

Metabolism

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58
Q

What is a solvent?

A

A substance which dissolves a solute resulting in a solution.

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59
Q

What does a ‘high heat capacity’ mean? (with water)

A
  • A large increase in temperature will result in a small rise in water temperature
  • Water is good at maintaining a persistent temperature despite large fluctuations in the environment
  • Buffers temperature changes within living organisms
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60
Q

What property of ice is beneficial to aquatic organisms?

A

When water freezes it becomes less dense, so it forms on the surface of ponds. Other liquids would build up at the bottom. Insulates from the cold.

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61
Q

What does cohesion mean?

A

How water molecules stick together

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62
Q

What is surface tension?

A

The connection (cohesion) of water molecules on the surface because they are more attracted to each other than the air.

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63
Q

Where do inorganic ions occur (biologically speaking)?

A

In the cytoplasm and body fluids of organisms

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64
Q

What does pH determine?

A
  • The potential for hydrogen
  • High concentration of hydrogen ions = low pH
  • Low concentration of hydrogen ions = high pH
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65
Q

How many iron ions does one molecule of haemoglobin contain?

A

4

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66
Q

What inorganic ion associates itself with haemoglobin?

A

Iron ions (Fe2+)

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67
Q

How many O2 molecules can join onto a molecule of haemoglobin (with iron)

A

8

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68
Q

What is co-transport

A
  • 2 substances simultaneously transported across a membrane by a protein, a symport
  • Na/K pump helps for sodium and glucose to be co transported in epithelial cells of intestines
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69
Q

What is important about water cohesion for plants?

A

Water is cohesive, allowing it to flow up xylem in transpiration

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70
Q

What is ATP?

A
  • Adenosine triphosphate
  • A nucleotide base adenine, a ribose sugar and three phosphate groups
  • An energy source for cells, made from glucose
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71
Q

How does ATP become ADP?

A

When one of the phosphate ions is hydrolysed, releasing a phosphate ion (Pi)

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72
Q

What are the monomers of proteins?

A

Amino Acids

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73
Q

Which 4 elements are always present in proteins?

A

Carbon, Hydrogen, Nitrogen + Oxygen

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74
Q

What is the Amine group of proteins?

A

NH2 on the left hand side

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75
Q

What is the Carboxyl group of proteins?

A

COOH on right hand side

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76
Q

What is the Variable group of proteins?

A

‘R’ group on the top (20 different types)

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77
Q

What is the primary structure of proteins?

A

The number and sequence of amino acids joined by peptides bonds.

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78
Q

What bond joins two amino acids? How is it formed?

A

A peptide bond formed by condensation reactions and broken by hydrolysis

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79
Q

What causes chains of amino acids to fold?

A

+ve and -ve charges of the R groups attract to opposite charges.

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80
Q

What are extra features of some R groups?

A
  • Positive and negative charges
  • Second carboxyl and anime groups
  • Disuphide bond
  • Hydrophobic/phillic
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81
Q

How can some properties of R groups of amino acids help separate them out?

A
  • Chromatography can separate amino acids by size and polarity whist suspended within an organic solvent
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82
Q

How do you calculate the Retardation factor (Rf value)?

A

Distance moved by spot / distance moved by solvent

83
Q

What is the secondary structure of proteins?

A

The folding of proteins due to H bonds forming between amino acids

84
Q

What are the two different arrangements of secondary structures of proteins?

A
  1. Alpha helix
    - H bonds between each peptide link
    - Strong, fibrous proteins
  2. Beta pleating
    - Sheets with H bonds, flexible
85
Q

What is the tertiary structure of proteins?

A
  • Further folded to form a 3D structure

- Includes H, disulfide and ionic bonds

86
Q

What are dislufide bonds (protein)?

A

Strong bonds which occur between sulphur atoms in R groups

87
Q

What are ionic bonds (protein)?

A
  • Form between carboxyl groups and amino groups not used in peptide bonds
  • Easily broken by changes in pH
88
Q

What are hydrogen bonds (protein)?

A
  • Bonds between Hydrogen atoms in Amino acids and R groups

- Weak alone but strong in numbers

89
Q

Why is having Hydrophobic and hydrophillic side chains on amino acids useful?

A
  • Hydrophillic sides will face outwards on cell membranes
  • Hydrophobic sides face inside, away from water
  • Helps to arrange proteins in the phospholipid bilayer
90
Q

What is the quaternary structure of proteins?

A

Proteins with more than one polypeptide chain, sometimes includes a non-protein prosthetic group
eg Haemoglobin

91
Q

What is a globular protein?

A

Tertiary structure is a round 3D shape and small and soluble. Eg enzymes

92
Q

What are the 8 functions of proteins?

A
  1. Anti bodies (immune response
  2. Muscle proteins (contraction)
  3. Enzymes (metabolism)
  4. Structural proteins
  5. Transport proteins (haemoglobin)
  6. Protein synthesis (ribosome proteins)
  7. Membrane proteins (receptor/transport proteins)
  8. Hormones
93
Q

What is the test for proteins? What would a positive result loom like?

A

The biuret test

  • Add sodium hydroxide
  • Add 1% copper sulfate
  • Positive result = Purple
  • Negative (no change = blue)
94
Q

Is the biuret test quantitative?

A

No, it is qualitative because only positive/negative

95
Q

What is anabolic metabolism?

A

Building up i.e. A+B -> AB

96
Q

What is catabolic metabolism?

A

Breaking down AB -> A+B

97
Q

What is meant by activation energy?

A

The energy needed for a reaction to start/proceed

98
Q

What is an enzyme

A

An organic catalyst which speeds up the rate of a reaction whilst remaining unchanged

99
Q

How does an enzyme-substrate complex (ESC) form?

A

Enzyme (E) combines with the reactant (Substrate S)

100
Q

Why do reactions occur faster with enzymes?

A

The activation energy is less than the alternative without the enzyme

101
Q

What was the old theory for enzyme action?

A

The lock and key theory

102
Q

What kind of protein structure are enzymes?

A

A tertiary structure with ionic, disulfide and hydrogen bonds

103
Q

Enzyme active sites and the substrates are said to have a ? shape

A

A complementary shape

104
Q

What was wrong with the old lock and key model for enzyme action?

A

Lock and key did not explain how other molecules (inhibitors) could fit to other parts of enzymes

105
Q

What is the induced fit model for enzyme action?

A
  • Substrates combine with enzymes
  • Active site of enzyme changes shape slightly
  • Strain exerted on substrate, distorting bonds and lowing the activation energy needed
106
Q

What is meant by “turn over number”?

A

The number of substrate molecules converted into products each minute. Enzymes work VERY quickly

107
Q

Name 4 key properties of enzymes.

A
  1. Work very quickly
  2. Unchanged by reactions
  3. Work in both directions (depending on conc)
  4. Specific to substrates
108
Q

What factors affect enzymes?

A
  • Temperature
  • pH
  • Substrate concentration
  • Enzyme concentration
  • Inhibitors
109
Q

What is the rate of reaction for all enzymes at 0 degrees C? Why is this?

A
  • The rate is 0

- There are no collisions between enzymes and substrates because there is no kinetic energy

110
Q

What happens to the rate of enzyme action as temperature increases (UP TO OPTIMUM)? Why?

A
  • Rate increases as temperature increases
  • Due to more kinetic energy
  • Substrates move more and collide with enzymes more regularly
  • Reduces activation energy
  • More ESCs
111
Q

What happens to the rate of enzyme action as temperature increases (BEYOND OPTIMUM)? Why?

A
  • H and ionic bonds within the tertiary structure break due to too much heat and thus kinetic energy
  • Tertiary structure is lost
  • Enzyme denatures, active site changes shape and less ESCs form
  • Disulfide bond do not break
112
Q

What happens once the tertiary structure of an enzyme is lost?

A

It is permanently damaged and stops working indefinitely

113
Q

What similarities and differences are there regarding “effect of pH on enzyme rate” graphs for different pHs?

A
  • The graph shape is always the same for all enzymes

- The optimum pH varies depending on enzymes

114
Q

What is the effect of a low pH on enzymes?

A
  • At low pH lots of H+ ions present
  • Ionic and H bonds break
  • Enzyme denatures because the tertiary structure is lost and the active site changes shape
  • Less ESCs form
115
Q

What is the effect of a high pH on enzymes?

A
  • Many OH- ions present
  • Ionic and H bonds break
  • Enzyme denatures because the tertiary structure is lost and the active site changes shape
  • Less ESCs form
116
Q

As substrate concentration increases and enzymes concentration is constant, what is the limiting factor?

A
  • Initially the substrate concentration

- Once substrate concentration exceeds enzyme concentration, enzymes concentration becomes the limiting factor

117
Q

Name the 2 types of inhibitor to enzymes.

A

Competitive and non-competitive inhibitors

118
Q

What do competitive inhibitors do?

A

Compete with the substrate for the enzymes active site, temporarily inhibiting enzymes action

119
Q

Name 4 key features of competitive inhibitors.

A
  1. Substrate and inhibitors have SIMILAR SHAPES
  2. COMPLEMENTARY to shape of enzyme active site
  3. If inhibitor goes into active site the substrate is unable to bind
  4. No ESCs are made
120
Q

True or false; Competitive inhibitors have the same shape as substrates

A

FALSE

They have a SIMILAR shape

121
Q

What happens to the amount of competitive inhibition when you add more substrate?

A

Less competitive inhibition

122
Q

Do non-competitive inhibitors have a similar shape to substrates.

A

No, non-competitive inhibitors bind to receptor sites elsewhere on the enzyme

123
Q

How do non-competitive inhibitors inhibit enzymes?

A
  • Bind to receptor sites on enzymes
  • Changes shape of enzyme
  • Substrates cannot bind to active sites
  • No longer complementary
  • No ESCs form
124
Q

What do cells need to do in order to efficiently regulate metabolism?

A

Needs to inhibit reactions

125
Q

How do cells effectively inhibit reactions

A

With metabolic reactions/pathways and inhibition

126
Q

Which organelle makes enzymes?

A

Ribosomes - enzymes are proteins

127
Q

Where to intracellular enzymes act?

A

Inside cells

128
Q

Where to extracellular enzymes act?

A

Outside cells

129
Q

What is digestion?

A
  • The chemical digestion and physical breakdown of foods

- Large molecules are hydrolysed by enzymes to produce smaller molecules to be absorbed and assimilated

130
Q

Why do enzymes only catalyse one reaction?

A

Because only one complementary substrate will fit into the active site

131
Q

Does increasing the concentration of substrates reduce competitive inhibition?

A

Yes. There is a higher chance that the substrates will get to active site + form ECS before the inhibitor

132
Q

Does increasing the concentration of substrates reduce NON-competitive inhibition?

A

No. The tertiary structure is changed, enzyme changes shape so no enzymes will bind to active site and form ESCs

133
Q

What are two methods of measuring the rate of an enzyme controlled reaction?

A
  1. Measure how fast the product is made

2. Measure how fast the substrate is broken down

134
Q

How can you calculate the rate of reaction from a graph?

A

By drawing tangent then dy/dx

135
Q

What is the genereic structure of all nucleotides?

A
  • A phosphate group
  • A pentose sugar (5 Carbon atoms)
  • Nitrogen - containing organ base
136
Q

What are the four bases found in DNA?

A

Adenine, THYMINE (DNA only), Guanine and Cytosine

137
Q

What are the four bases found in RNA?

A

URACIL (RNA only), Adenine, Guanine and Cytosine

138
Q

How do the three components of DNA join up?

A

By condensation reactions

139
Q

Where does the phosphate group and the nitrogenous base join the pentose sugar?

A

Phosphate group to C4

Base to C1

140
Q

How does a phosphodiester bond form?

A

Two mononucleotides join together by a condensation reaction from C3 to the phosphate group

141
Q

What is a long chain of nucleotides called?

A

A polynucleotide

142
Q

What did scientists use to believe stored hereditary material (before DNA)? Why?

A

They used to believe that proteins stored genetic material because they are very diverse (20 amnino acids compared to 4 nucleotides)

143
Q

Who worked out the structure of DNA?

A

Franklin, Watson and Crick

144
Q

What is the pentose sugar in DNA?

A

Deoxyribose

145
Q

What is meant by double stranded DNA?

A

DNA (always) has two polynucleotide stands

146
Q

How are the two stands of DNA held together?

A

Hydrogen bonds between complementary base pairs

147
Q

How many hydrogen bonds are there between Adenine and Thymine?

A

2

148
Q

How many hydrogen bonds are there between Cytosine and guanine?

A

3

149
Q

Why are the strands in DNA said to be ‘anti-parallel’?

A

The nucleotide stands run in opposite directions to each other

150
Q

Why is the sugar-phosphate backbone important for DNA?

A
  • Stability and strength

- Backbone protects bases on inside form chemical/physical damage

151
Q

DNA is a stable molecule. Why is this important?

A
  • Does not change

- Info can be passed on accurately

152
Q

Why is the double helix of DNA useful?

A

Compact

153
Q

Why is the base sequence important?

A

Codes for polypeptides (unique codes)

154
Q

By what method does DNA replicate?

A

Semi-conservatively

155
Q

Why is complementary DNA base paring important?

A

Ensures accurate replication takes place

156
Q

Why does DNA have weak hydrogen bonds between complementary base pairs?

A

Allows for the 2 strands to be separated easily by DNA helicase (Enzyme)

157
Q

What were the two theories behind DNA replication?

A

Conservative and semi-conservative replication

158
Q

What was involved in conservative DNA replication?

A

The old strand of DNA did not ‘unzip’ but instead was retained along with a new strand

159
Q

Who conducted an experiment to prove that DNA replicated semi-conservatively?

A

Meselsohn and Stahl

160
Q

What was done to prove that DNA replicated semi-conservatively?

A
  • E. coli fed on two isotopes of nitrogen (14N and 15N)
  • ‘Heavy’ DNA built up at bottom
  • Repeated for next generations in 14N only, ‘heavy’ DNA drained out by semi-conservative replication
161
Q

What enzyme breaks the hydrogen bonds between bases in DNA?

A

DNA Helicase

162
Q

What enzyme joins 2 new nucleotides together after replication?

A

DNA Polymerase

163
Q

What does the enzyme DNA helicase do?

A

Unzips the double helix, breaks hydrogen bonds between the base pairs

164
Q

How do new nucleotides join unzipped DNA in replication?

A
  • Unzipped DNA strands act as templates

- Free nucleotides attracted to exposed base pairs

165
Q

What happens once the free nucleotides become attracted to exposed base pairs in DNA replication?

A

Hydrogen bonds form between the complementary base pairs

166
Q

What enzyme joins new nucleotides in the last stage of DNA replication?

A

DNA polymerase

167
Q

Which base of DNA pairs with thymine?

A

Adenine

168
Q

Which base of DNA pairs with cytosine?

A

Guanine

169
Q

What type of reaction joins two nucleotides with DNA polymerase?

A

A condensation reation

170
Q

What bond joins two nucleotides in a strand?

A

Phosphodiester bonds

171
Q

Is RNA double stranded?

A

No. It is a single polynucleotide

172
Q

What is the sugar in RNA?

A

Ribose

173
Q

What base does RNA have instead of Thymine?

A

Uracil

174
Q

What are the 3 main types of RNA?

A

Messenger (mRNA)
Ribosomal (rRNA)
Transfer (tRNA)

175
Q

What is the role of messenger RNA (mRNA)?

A

Transfers info from DNA to ribosomes

176
Q

What is the role of ribosomal RNA (rRNA)?

A

Associated with proteins, rRNA makes up ribosomes

177
Q

What is the role of transfer RNA (tRNA)?

A

Carries specific amino acids to ribosmomes during protein synthesis

178
Q

Is DNA a ‘long molecule’?

A

Yes, much longer than RNA

179
Q

Does RNA have hydrogen bonds like DNA?

A

Sometimes. tRNA has hydrogen bonds in loops of the SINGLE STRAND

180
Q

What is the role of DNA?

A
  • Codes for polypeptides

- Holds genetic info

181
Q

What is the initial source of energy for all living organisms?

A

The sun

182
Q

What is the word equation for photosynthesis?

A

Carbon dioxide + water -> Glucose + oxygen

183
Q

How is ATP made?

A

Glucose is oxidised to make adenosine triphosphate

184
Q

What are the 3 parts of ATP?

A
  • Adinine
  • Ribose sugar
  • 3 phosphate groups
185
Q

Why does ATP have a low activation energy?

A

3 phosphate groups have unstable bonds between them, easily broken

186
Q

How is one of the phosphate groups in ATP removed?

A

Water is added (hydrolysis) and enzyme ATP hydrolase

187
Q

What enzyme is involved in forming ATP from ADP?

A

ATP synthase (water also added, condensation reaction)

188
Q

Under what circumstances is ATP synthesized (made from ADP + Pi)?

A
  1. Photosynthesis (in chlorophyll)

2. During respiration

189
Q

What is the process called whereby ATP is synthesized in photosynthesis?

A

Photophosphorylation

190
Q

Why can’t ATP be stored?

A

Because of instability of the phosphate bonds

191
Q

ATP cannot be used as a long-term energy source - so what can?

A

Fats and carbohydrates

192
Q

Why is ATP often useful in Cells?

A

Provides an immediate energy source

193
Q

Is ATP soluble?

A

Yes. In cytoplasm

194
Q

Does ATP leave cells?

A

NO. Stays within the cell it was made

195
Q

Why is ATP better than glucose as an immediate energy source?

A
  • Glucose is difficult to break down -takes time

- Less energy is released by hydrolyzing ATP, but more manageable and instant

196
Q

For what processes is ATP used for within cells?

A
  • metabolic processes
  • Movement
  • Active transport
  • Secretion
  • Activation of molecules
197
Q

How is ATP used in metabolic processes?

A

Builds molecules from small molecules

eg Proteins, DNA, glycogen and starch

198
Q

How is ATP used in movement?

A

Muscle contraction

199
Q

How is ATP used in active transport?

A

Changes the shape of carrier proteins so that molecules or ions can move against the concentration gradient

200
Q

How is ATP used in secretion?

A

Formation of lysosomes/vesicles for exocytosis

201
Q

How is ATP used in activation molecules?

A

Pi released from APT can be hydrolyzed to make other compounds more reactive, lowering activation energy

202
Q

What is translation?

A

When RNA is read in Ribosomes to make polypeptides (proteins)

203
Q

What is a phosphodiester bond?

A
  • A bond joining 2 nucleotides

- Contains 2 ester bonds and the phosphate group

Biology (10 decks)

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