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Biological Molecules Flashcards

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1
Q

What are carbohydrates primarily composed of?

A

Carbon, hydrogen, and oxygen

Carbohydrates follow the general formula (CH₂O)n.

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2
Q

What is a monomer of carbohydrates called?

A

Monosaccharide

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3
Q

What is the general formula for monosaccharides?

A

(CH₂O)n

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4
Q

Name three examples of monosaccharides.

A
  • Glucose
  • Galactose
  • Fructose
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5
Q

How many isomers does glucose have?

A

Two: alpha and beta

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6
Q

What is a reducing sugar?

A

A sugar that can donate electrons to another chemical

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7
Q

What is the purpose of Benedict’s reagent?

A

To test for reducing sugars

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8
Q

What forms when a reducing sugar reacts with Benedict’s reagent?

A

An insoluble red precipitate of copper(I) oxide

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9
Q

Describe the steps of the Benedict’s Test.

A
  • Add 2 cm³ of the food sample to a test tube
  • Add an equal volume of Benedict’s reagent
  • Heat the mixture in a gently boiling water bath for 5 minutes
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10
Q

Fill in the blank: A reducing sugar can _______ another chemical.

A

reduce

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11
Q

True or False: Maltose is a reducing sugar.

A

True

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12
Q

What are disaccharides?

A

Pairs of monosaccharides

Examples include maltose (glucose + glucose), lactose (glucose + galactose), and sucrose (glucose + fructose).

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13
Q

What happens when monosaccharides join?

A

A molecule of water is removed in a condensation reaction, forming a glycosidic bond.

This process connects monosaccharides to form disaccharides.

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14
Q

What is hydrolysis in the context of disaccharides?

A

The addition of water to a disaccharide that breaks the glycosidic bond, releasing monosaccharides.

This reaction is the reverse of the condensation reaction.

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15
Q

Define polysaccharides.

A

Polymers formed from the joining of many monosaccharides by glycosidic bonds.

They are large, insoluble molecules suitable for storage.

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16
Q

What role do some polysaccharides like cellulose play?

A

Provide structural support to plant cells.

Cellulose is not used for storage.

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17
Q

What are the characteristics of fructose?

A

Very soluble, main sugar in fruits, sweeter than glucose.

Fructose is a monosaccharide.

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18
Q

How does galactose compare to glucose in terms of solubility?

A

Galactose is not as soluble as glucose.

It plays an important role in the production of glycolipids and glycoproteins.

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19
Q

List the characteristics of sugars.

A
  • Sweet taste
  • Low molecular mass
  • Soluble in water
  • Used for energy

Sugars are typically simple carbohydrates.

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20
Q

What are the characteristics of non-sugars?

A
  • Non-sweet taste
  • Insoluble in water
  • High molecular mass
  • Important role in storage and structure

Non-sugars include complex carbohydrates.

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21
Q

Structure of starch

A
  • Made up of chains of a-glucose monosaccharides linked by glycosidic bonds that are formed by condensation reactions
  • these chains can be branched or unbranched
    -> the un branched chain is wound into a coil (helix) which makes the molecule compact
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22
Q

The pairs of monosaccharides

A
  • glucose + glucose -> maltose
  • glucose + fructose -> sucrose
  • glucose + galactose -> lactose
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23
Q

How the properties of starch help it

A
  • insoluble -> doesn’t affect water potential so water isn’t drawn into the cell by osmosis
  • large -> can’t diffuse out of cells
  • compact -> lots can be stored in small space
  • when hydrolysed is form a-glucose -> easily transported and readily used in respiration
  • branded form has many ends -> enzymes can act simultaneously (large SA for hydrolysis back to glucose)
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24
Q

Why does glycogen have more branches than starch

A

Because animals have a higher metabolic rate than plants and so higher respiratory rate

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25
Q

Where is glycogen found

A

In bacteria and animals

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26
Q

Where is glycogen stored in animals

A

In small granules mainly in muscles and liver

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27
Q

Properties of glycogen

A
  • insoluble
  • compact
  • large
  • more branched than starch
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28
Q

What monomers are cellulose made of

A

B-glucose

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29
Q

Structure of cellulose

A
  • instead of coiled chain like starch it forms straight, long unbranched chains
    -> these run parallel to each other which allows H2 bonds to form cross-linkages
    -> individually the H2 bonds are weak but collectively very strong
  • the cellulose molecules are grouped to form microfibrils
  • cellulose also prevents the cell from bursting as water enters by osmosis
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30
Q

Properties of cellulose

A
  • Made from B-glucose -> to form long straight unbranched chains
  • Chains run parallel to one another -> are cross-linked by H2 bonds that add collective strength
  • Grouped to form microfibrils -> provides more strength
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31
Q

What are lipids primarily composed of?

A

Carbon, hydrogen, and oxygen

Lipids have a high proportion of carbon and hydrogen relative to oxygen.

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32
Q

Are lipids soluble in water?

A

No, they are insoluble in water

Lipids are soluble in organic solvents like alcohol and acetone.

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33
Q

What are the main groups of lipids?

A
  • Triglycerides (fats and oils)
  • Phospholipids
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34
Q

What role do phospholipids play in cellular membranes?

A

Contribute to the flexibility of membranes and transfer of lipid-soluble substances across them.

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35
Q

What is one source of energy in the body?

A

Lipids

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36
Q

What function do lipids serve in waterproofing?

A

Insoluble in water

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37
Q

How do fats contribute to insulation?

A

Fats are poor conductors of heat and act as electrical insulators in the myelin sheath around nerve cells.

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38
Q

What protective role do lipids have in the body?

A

Fat is often stored around organs.

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39
Q

What are triglycerides formed from?

A

3 fatty acids and 1 glycerol

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40
Q

What type of reaction forms ester bonds between fatty acids and glycerol?

A

Condensation reaction

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41
Q

What products are formed from the hydrolysis of a triglyceride?

A

Glycerol and 3 fatty acids

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42
Q

Fill in the blank: A triglyceride is composed of _____ fatty acids and one glycerol.

A

3

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43
Q

True or False: Hydrolysis of triglycerides results in the formation of water.

A

True

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44
Q

5 roles of lipids

A
  • flexibility of membranes + transfer of lipid-soluble substances across them
  • source of energy
  • waterproofing
  • insulation
  • protection
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45
Q

What is the primary component that varies among different fats and oils?

A

Variations in the fatty acids

There are over 70 different fatty acids, each contributing to the properties of fats and oils.

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46
Q

What functional group is present in all fatty acids?

A

Carboxyl (-COOH) group

This group is attached to a hydrocarbon chain in fatty acids.

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47
Q

What characterizes a saturated fatty acid?

A

No C double bonds in the hydrocarbon chain

Saturated fatty acids are solid at room temperature.

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48
Q

What defines a monounsaturated fatty acid?

A

Presence of a single double bond

This type of fatty acid has one double bond in its hydrocarbon chain.

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49
Q

How is a polyunsaturated fatty acid characterized?

A

More than one double bond present

Polyunsaturated fatty acids tend to be liquid at room temperature.

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50
Q

What effect do double bonds have on the structure of fatty acids?

A

Cause the molecule to bend

This bending prevents tight packing, making them liquid at room temperature.

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51
Q

What is a significant property of triglycerides related to energy?

A

High ratio of energy-storing C-H bonds to C atoms

This makes triglycerides an excellent source of energy.

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52
Q

What is the mass-to-energy ratio of triglycerides?

A

Low mass to energy ratio

This allows for more energy to be stored in a smaller volume.

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53
Q

Why are triglycerides considered good storage molecules?

A

They can store more energy in a small volume

This reduces the mass animals have to carry.

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54
Q

What is the solubility of triglycerides in water?

A

Insoluble in water

This characteristic prevents them from affecting water potential.

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55
Q

What is the ratio of H:O atoms in triglycerides, and what does it provide?

A

High ratio of H:O atoms; provides a source of water when oxidized

This is important for energy metabolism in animals.

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56
Q

What are phospholipids?

A

Lipids similar to lipids but one fatty acid is replaced by a phosphate molecule

Phospholipids are essential components of cell membranes.

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57
Q

What is the hydrophilic part of a phospholipid called?

A

Hydrophilic head

The hydrophilic head attracts water.

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58
Q

What is the hydrophobic part of a phospholipid called?

A

Hydrophobic tail

The hydrophobic tail repels water and mixes readily with fat.

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59
Q

What characteristic of phospholipids allows them to form a bilayer in an aqueous environment?

A

Their polar nature

The hydrophilic heads orient towards water while the hydrophobic tails orient away.

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60
Q

What structure do phospholipids create within cell-surface membranes?

A

A bilayer

This bilayer forms a hydrophobic barrier between the outside and inside of a cell.

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61
Q

How do hydrophilic heads behave in relation to water?

A

They are attracted to water

This allows them to hold at the surface of the cell-surface membrane.

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62
Q

What role do glycolipids play in cell membranes?

A

They are important in cell recognition

Glycolipids are formed by the combination of phospholipids with carbohydrates.

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63
Q

Fill in the blank: Phospholipids have a _______ head and a _______ tail.

A

hydrophilic; hydrophobic

This dual nature is crucial for their function in membranes.

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64
Q

Why are saturated fats more unhealthy

A

Because they are densely compacted

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65
Q

What are the monomers of proteins

A

Amino acids

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66
Q

How is a dipeptide formed

A

When 2 amino acids join

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67
Q

How is a polypeptide formed

A

When more than 2 amino acids join

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68
Q

What makes up proteins

A

1 or more polypeptides

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69
Q

What makes up amino acids

A
  • a carboxyl group (-COOH)
  • an amine or amino group (-NH2)
  • an R group (variable side group)
  • a H
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70
Q

What differentiates amino acids

A

What makes up their R group

-> 20 different amino acids

71
Q

Why is glycine special

A

It’s the only amino acid with no C in its side group -> it’s R group is just 1 hydrogen atom

72
Q

What is a condensation reaction

A

Joining molecules together by removing water

73
Q

Hydrolysis

A

Breaking down molecules by adding water r

74
Q

How are polypeptides formed

A

When amino acids link together by condensation reactions

-> a molecule of water is released and the bonds formed between amino acids are called peptide bonds
(The reverse happens in digestion)

75
Q

The 4 protein structural levels

A
  • primary structure
  • secondary structure
  • tertiary structure
  • quaternary structure
76
Q

Primary structure of proteins and

A

The sequence of amino acids in the polypeptide chains

-> determines its shape and function

77
Q

Secondary structure of proteins

A

The polypeptide chain doesn’t stay flat and straight - hydrogen bonds form between the amino acids in the chain

-> this makes it coil into an alpha helix or fold into a beta pleated sheet

78
Q

Tertiary structure of proteins

A

When the coiled or folded chain is coiled or folded even more, more bonds form:

• Disulfide bridges - fairly strong and so not easily broken
• Ionic bonds - formed between any carboxyl and amino groups that aren’t involved in forming peptide bonds
-> weaker than disulfide bonds and easily broken by changes in pH
• Hydrogen bonds - numerous but easily broken

  • for single polypeptide chain proteins this structure forms their final 3D structure
79
Q

Quaternary structure of proteins

A

Some proteins are made of several different polypeptide chains held together by bonds
-> this structure is the way these chains are assembled
-> for proteins formed from multiple polypeptide chains this is the final 3D structure

80
Q

2 types of proteins

A

• Fibrous proteins (eg collagen) - have structural functions
• Globular proteins (eg enzymes, haemoglobin) - carry out metabolic function

81
Q

Protein Functions

A
  • enzymes
  • antibodies
  • transport proteins
  • structural proteins
82
Q

Proteins as enzymes

A
  • usually spherical shape due to tight folding of polypeptide chains
  • soluble + often have roles in metabolism
83
Q

Proteins as antibodies

A
  • involved in immune response
  • made up of 2 light polypeptide chains + 2 heavy ones bonded together
  • have variable regions -> the amino sequence in the regions vary a lot
84
Q

Proteins as transport proteins

A

E.g. channel proteins are present in cell membranes
-> contain hydrophobic + hydrophilic amino acids which cause the protein to fold up and forms channel
-> they transport molecules and ions across membranes

85
Q

Proteins as structural proteins

A
  • strong with long polypeptide chains parallel to each other with cross-links
  • includes keratin (in hair + nails) and collagen (in connective tissue)
86
Q

Biuret test

A
  • solution needs to be alkaline so add a few drops of NaOH solution
  • then add copper (II) sulfate solution
    -> if protein is present it will turn purple from blue
87
Q

What is activation energy

A

The minimum amount of energy required for a reaction to take place

88
Q

What does an enzyme do

A

Lower the activation energy and so speeds up to reaction without being used up

89
Q

Explain why the quaternary structures of collagen makes it a suitable molecule for a tendon

A

It’s made up of 3 polypeptide chains wound together making it strong in the direction of pull of the tendon

90
Q

How do the cross-linkages between the amino acids of polypeptide chains increase the strength and stability of a carbon fibre

A

Prevents the individual polypeptide chains sliding past each other

91
Q

Explain why this arrangement of collagen molecule is necessary for efficient functioning of a tendon

A

The junctions between the adjacent molecules are weak and if they joined back where it started they could easily break

92
Q

Globular proteins

A
  • have spherical shape
  • soluble in water
  • tend to have a biochemical function over a structural one
  • all enzymes are globular proteins
93
Q

What reactions do enzymes catalyse

A

Both anabolic (building up) and catabolic (breaking down) reactions

94
Q

Where does enzyme action occur

A

Both intracellularly (eg DNA replication) and extracellularly (eg digestion)

95
Q

Lock and key model

A

Substrate is perfectly complimentary to active site of enzyme then substrate breaks into product molecules

-> substrates only fits 1 active site (fixed shape)

96
Q

Limitation of lock and key model

A

Rigid structure instead of flexible

97
Q

Induced fit theory

A
  • Substrate molecule isn’t exact shape of the enzyme’s active site
  • enzyme molecule changes shape slightly as the substrate molecule binds with the active site
  • enzyme then resumes original shape and active site is free to accept another pair of substrate molecules
98
Q

What does the induced fit theory propose

A

That the active site forms as the enzyme and substrate interact

99
Q

How do enzymes cause activation energy to decrease

A

The enzyme is flexible and can mould itself around the substrate -> as it changes shape, it puts strain on the substrate molecule which distorts a particular bond(s) in the substrate causing the activation energy needed to break the bond to decrease

100
Q

Factors that affect enzyme action

A
  • temp
    -pH
    -substrate conc
  • enzyme conc
101
Q

Effect of temp on enzymes

A
  • Increase in kinetic energy so molecules collide more frequently (RoR increase)
  • eventually denatures as the weak H bonds break and tertiary structure unravels
    -> active site distorts so its not complimentary to the substrate
102
Q

Effect of pH on enzymes

A
  • A change alters the charges on the amino acids that make up the active site
  • they denature due to weak H bonds breaking which distorts the active site
  • this makes it not complimentary to the substrate
103
Q

Effect of substrate conc in enzymes

A

The number of substrate exceeds the number of enzymes

104
Q

Effect of enzyme conc on enzymes

A

The number of enzymes exceeds the number of substrates conc

105
Q

What are inhibitors

A

Substances that interfere with enzyme activity

106
Q

Competitive inhibitor

A
  • molecular shape similar to substrate
    -> so they compete for the active site with the normal substrate
  • if the normal substrate conc is increased the effect of the inhibitor is reduced
107
Q

Non-competitive inhibitor

A
  • Attach to a site on the enzyme which isn’t the active site
    -> this leads to a change in the shape of the active site so the substrate can no longer occupy it
  • as the substrate and inhibitor aren’t competing for the same site an increase in substrate conc doesn’t decrease the effect of the inhibitor
108
Q

What is an inorganic ion

A

Charged molecule that doesn’t contain C-H bonds

109
Q

What are inorganic ions used for

A

Central to the structure and metabolism or all living organisms, participating in metabolic reactions and combining with organic molecules to form complex molecules

110
Q

Cation

A

A positive ion

111
Q

Anion

A

A negative ion

112
Q

Sodium (Na+)

A
  • major extracellular cation in animal cells
  • involved in transmission of nerve impulses and in fluid + electrolyte balance
  • in plants, its involved in maintaining cell turgid + in opening and closing the stomata
113
Q

Potassium (K+)

A
  • main intracellular cation in all cell types
  • involved in heart function + transmission of nerve impulses
  • in plants, it’s involved in controlling stomata opening via guard cells
114
Q

Ammonium (NH4+)

A
  • an important source of nitrogen for many plants
  • generated in the kidney as part of acid-base regulation
115
Q

Iron (Fe3+/Fe2+)

A
  • iron-binding proteins are involved in redox proteins, electron transport, and in the transport of oxygen as a component of haemoglobin
116
Q

Hydrogen (H+)

A
  • important in acid-base chemistry
  • establish trans-membrane electrochemical gradients which can be used to generate ATP
117
Q

Calcium (Ca2+)

A
  • in vertebrates, it’s a component of teeth and bone and is involved in muscle contraction, blood clotting, activation of some enzymes, and cell signalling
  • in plants, it’s a component of the cell wall
118
Q

Hydrogen carbonate (HCO3-)

A
  • alkaline and acts as a pH buffer in the body to maintain acid-base homeostasis
  • a buffer is a molecule that can bind or release hydrogen ions in order to maintain a particular pH
  • released from the pancreas to neutralise the acidic chyme entering the intestine from the stomach
119
Q

Chloride (Cl-)

A
  • essential electrolyte present in all body fluids, involved in fluid balance, acid-base balance, and to form HCl in gastric juice
120
Q

Nitrate (NO3-)

A
  • important source of nitrogen for plants
    BUT anaimls obtain their nitrogen by eating other organisms
  • nitrogen is a component of amino acids and nucleotides
121
Q

Phosphate (PO4 3-)

A
  • component of phospholipids, nucleotides and ATP
  • combined with calcium as calcium phosphate in bones and teeth
122
Q

Hydroxide (OH-)

A

Important in acid-base chemistry
- central to many biological reactions

123
Q

ATP

A

Adenosine Triphosphate

124
Q

Structure of ATP

A

A phosphorylated macromolecule w/ 3 parts:
• adenine - a nitrogen-containing organic base
• ribose - a sugar molecule w/a 5 carbon ring structure (pentose) which all else is attached to
• phosphates - a chain of 3 phosphate groups

125
Q

What does adenine and ribose make

A

Adenosine

126
Q

What does adenine, ribose and 1 phosphate group make

A

Adenosine monophosphate (AMP)

127
Q

What does adenine, ribose and 2 phosphate groups make

A

Adenosine diphosphate (ADP)

128
Q

What does adenine, ribose and 3 phosphate groups make

A

Adenosine triphosphate (ATP)

129
Q

What is ATP also

A

A nucleotide

130
Q

What is significant about the phosphate groups in ATP

A

The bonds between them are unstable and so have a low activation energy, meaning they can be easily broken to release lots of energy

131
Q

How is ATP converted to ADP

A

Water is used in a hydrolysis reaction and the reaction is catalysed by the enzyme ATP hydrolase to break the bonds between the 2nd + 3rd phosphate groups

132
Q

How is ADP converted back to ATP

A

Energy can be used to add an inorganic phosphate to ADP to reform ATP -> this condensation reaction is catalysed by ATP synthase

133
Q

When does the synthesis of ATP from ADP occur

A
  • in chlorophyll-containing plant cells during photosynthesis (photophosphorylation)
  • in plants and animal cells during respiration (oxidative phosphorylation)
  • in plant and animals cells when phosphate groups are transferred from donor molecules to ADP (substrate-level phosphorylation)
134
Q

Why is ATP a better immediate energy source than glucose

A
  • the hydrolysis of ADP to ATP is a single reaction whereas the breakdown of glucose is a lot of reaction and so energy release is slower
  • each ATP molecule release less energy than each glucose molecule
    -> therefore they are more manageable quantities
135
Q

What organelle makes ATP and when

A

Mitochondria during aerobic respiration

136
Q

Role of ATP in metabolic processes

A

ATP provides the energy needed to build up macromolecules from their basic units eg AA to polypeptides

137
Q

Role of ATP in movement

A

ATP provides energy for muscle contraction

138
Q

Role of ATP in active transport

A

ATP provides the energy to change the shape of carrier proteins in plasma membranes -> allows ions/molecules to be moved against a conc gradient

139
Q

Role of ATP in secretion

A

ATP needed to form lysosomes necessary
-> in lysosomes enzymes are secreted

140
Q

Role of ATP in activation molecules

A

Inorganic phosphate released during hydrolysis of ATP can be used to phosphorylate other compounds in order to make them more reactive

-> lowering the activation energy in enzyme-catalysed reactions

141
Q

Why is ATP sometimes referred to as an immediate energy source

A

The phosphate bonds are unstable so it’s quick

142
Q

Explain how ATP can make an enzyme catalysed reaction take place more readily

A

Lowers the activation energy -> the inorganic phosphate

143
Q

3 roles of ATP in plant cells

A
  • photosynthesis
  • respiration
  • when phosphate groups are transferred from donor molecules to ATP
  • metabolism
    gene expression
144
Q

Why is water dipolar

A

The oxygen atom has a slight -ve charge whisky the hydrogen atoms have a slight +ve charge

145
Q

Hydrogen bonding in water

A

The attractive force between the opposite charges is called a hydrogen bond

146
Q

Water as a metabolite

A
  • used to break down many complex molecules by hydrolysis
  • produced in condensation reactions
  • chemical reactions take place in an aqueous medium
  • major raw material in photosynthesis
147
Q

Water as a solvent

A

Readily dissolves other substances:
-> gases eg oxygen and carbon dioxide
-> wastes eg ammonia and urea
-> inorganic ions + small hydrophilic molecules eg ATP, AA
-> enzymes whose reactions take place in solution

148
Q

Water with high heat capacity

A
  • molecules stick together > takes more energy to separate them than would be needed if water molecules didn’t bond to one another
149
Q

Water with a large latent heat of vaporisation

A
  • hydrogen bonding between water molecules -> requires lots of energy to evaporate 1g of water
150
Q

Water as cohesive

A
  • tendency of molecules to stick together
  • hydrogen bonds -> gives it large cohesive forces which allow water to be pulled up through a tube (eg xylem vessel)
  • water polar -> +ve hydrogen -ve oxygen
  • surface tension
151
Q

Describe how the properties of water allow a tree to survive

A
  • a metabolite
  • the water molecules stick together due to hydrogen bonding so waters bp is high (it buffers them against sudden temp changes)
  • water has large cohesive forces which allow it to be pulled up through the xylem so it can replace water that’s been evaporated in the leaf
  • it’s a major raw material in photosynthesis helping it to produce glucose
  • solvent -> can help transport mineral ions
152
Q

Describe how the properties of water allows humans to survive

A
  • evaporation of water eg sweat helps cooling as body heat is used to evaporate the water due to a lot of latent heat of vaporisation -> uses a lot of heat energy so cools you down removing heat
  • used in hydrolysis
  • produced in condensation reactions
  • dissolves in wastes like urea
  • can evaporate which helps control temp -> prevents enzymes denaturing - acts as a temp buffer
  • not easily compressive so provides support eg the skeleton
153
Q

What does RNA stand for

A

Ribonucleic acid

154
Q

What does DNA stand for

A

Deoxyribonucleic acid

155
Q

What does each nucleotide consist of

A

Phosphate group
Deoxyribose (pentose sugar)
Organic base

156
Q

What is the polymer made from the nucleotide monomers

A

DNA

157
Q

Double helix structure

A
  • adenine always bonds with thymine
  • guanine always bonds with cytosine
  • bases held together by hydrogen bonds
  • complementary base pairing
  • order of letters makes DNA code
158
Q

What are pyrimidines

A

Single ring bases - C and T

159
Q

What are purines

A

Double ring bases - A and G

160
Q

What joins A and T

A

2 hydrogen bonds

161
Q

What joins C and G

A

3 hydrogen bonds

162
Q

What does more GC mean in DNA and why

A

Means it is more stable and harder to split up as they form a base pair with 3 hydrogen bonds opposed to the 2 hydrogen bonds between AT

163
Q

How is a polynucleotide made

A

The phosphate bonds to the C of the deoxyribose sugar in a condensation reaction forming a phosphodiester bond which joins adjacent nucleotides together

164
Q

RNA structure

A
  • contains A, C and G but U (uracil) instead of T
  • the sugar is ribose not deoxyribose
  • it’s a single strand not double
  • different types: mRNA, tRNA, rRNA
165
Q

Name the 4 bases found in DNA and the bonds formed between them

A

Adenine, Guanine, Thymine, Cytosine
Hydrogen bonds

166
Q

Which molecules make up the backbone of a polynucleotide

A

Phosphate and deoxyribose

167
Q

What are the 3 differences between DNA and RNA

A
  • RNA contains uracil not thymine
  • RNA has ribose sugar not deoxyribose
  • RNA is single strand not double
168
Q

What is the structure of ATP

A

Adenine, ribose and 3 phosphate groups

169
Q

What does the hydrolysis of ATP produce

A

ADP

170
Q

Give the equation for the formation of ATP

A

ADP + inorganic phosphate -> ATP + water

171
Q

How is DNA stable

A
  • the phosphodiester backbones protects the more chemically reactive organic base
  • hydrogen bonds link the organic bases
172
Q

Function of DNA

A

It’s the hereditary material that passes on genetic material from generation to generation

173
Q

DNA adaptations for its function

A
  • very stable
  • only hydrogen bonds join the 2 strands -> can separate during DNA replication and protein synthesis
  • very large -> so carries a lot of genetic info
  • the base pairs are within the sugar-phosphate backbones -> so the genetic info is protected

Bio Alevel (5 decks)

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