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Biology > 1.1 Biological Molecules > Flashcards

1.1 Biological Molecules Flashcards

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1
Q

What is an inorganic ion?
What are they also called?
what are they needed for?

A

Something that has 1 or fewer carbon atoms.
often called minerals.
To survive

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2
Q

What is an organic ion?

A

Molecules that have 2 or more carbon atoms.

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3
Q

What is a macronutrient?
(example)

A

it is something needed in small concentrations
(magnesium/iron)

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4
Q

What is a micronutrient?
(example)

A

needed in minute concentrations
(copper/zinc)

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5
Q

what is the biological importance of magnesium?

A

-Important when making chlorophyll
-Essential for photosynthesis to make glucose

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6
Q

What happens if there is no chlorophyll?

A

The leaves will be yellow, (chlorosis)

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7
Q

What is the process of having less magnesium?

A

less magnesium-less photosynthesis-less glucose-less respiration-less ATP (energy) - less growth - DEATH OF PLANT

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8
Q

What do mammals need magnesium for?

A

Needed for their bones

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9
Q

What is the importance of iron?

A

iron is a component of haemoglobin (found in red blood cells)

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10
Q

What is haemoglobin needed for?

A

To transport oxygen

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11
Q

what does a lack of iron cause?

A

Anaemia

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12
Q

What are the symptoms of Anaemia?

A

-faint
-fatigue
-dizziness

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13
Q

What causes dizziness?

A

-less oxygen transported around the body,
- so less aerobic respiration,
-so less ATP

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14
Q

What is the importance of calcium?
(animals)

A

Important for structure in the bones and teeth of mammals. calcium hardens bones and teeth due to ossification.

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15
Q

what is the importance of calcium in plants?

A

component of plant cell walls

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16
Q

What is the importance of phosphate?
3 examples…

A

used for making nucleiotides (ATP/ DNA/ RNA)
part of phospholipids found in biological membranes
hardens bones

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17
Q

what are metabolic reactions

A

reactions that happen in cells

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18
Q

what is anabolism?
examples

A
  • Building molecules up
    (production of starch/glucose, DNA replication, protein synthesis)
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19
Q

What is catabolism?
examples

A

Breaking molecules down
(digestion of food decomposition)

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20
Q

what is a polymer?

A

when molecules are joined together in a repeating fashion. It is a larger more complex molecule.

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21
Q

what are all living organisms made from?

A

5 biological molecules

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22
Q

What are the five biological molecules?

A

-protein
-water
-carbohydrates
-nucleic acids
-lipids

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23
Q

does protein have monomer/polymer

A

yes

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24
Q

what’s the general name of the monomer of a protein?

A

amino acid

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25
Q

what’s the general name of the polymer of a protein?

A

polypeptide

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26
Q

what bonds to proteins have?

A

They have peptide bonds

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27
Q

does water have monomers and polymers?

A

No

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28
Q

is water a monomer or a polymer?

A

isn’t really a monomer or a polymer

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29
Q

does carbohydrates have monomer/polymers

A

yes

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30
Q

what’s the general name of the monomer of carbohydrates?

A

monosaccharide

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31
Q

what’s the general name of the polymer of carbohydrates?

A

polysaccharide

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32
Q

what bonds do carbohydrates have?

A

glycosidic bonds

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33
Q

do nucleic acid have monomers/polymers?

A

yes

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34
Q

what’s the general name of the monomer of nucleic acid?

A

nucleotide

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35
Q

what’s the name of the polymer of nucleic acid?

A

polynucleotide

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36
Q

name some nucleotides

A

ATP, DNA & RNA

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37
Q

Explain the structure of water.

A
  • 2 hydrogen atoms strongly covalently bonded to one oxygen atom
  • small in size
  • polar/dipole
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38
Q

explain bonds and charges within water

A

-hydrogen shares a pair of electrons with the oxygen\not shared equally

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39
Q

what does polar mean?

A
  • an unequal distribution of charge
  • oxygen is slightly negative, hydrogen slightly positive
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40
Q

what does delta mean?

A

slightly

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41
Q

what does dipole mean?

A

overall there is no charge

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42
Q

what are the hydrogen bonds in water responsible for

A

many of the properties of water

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43
Q

what causes a hydrogen bond to form?

A

the uneven distribution of charge allows a hydrogen bond to form. it forms between the hydrogen atom of one water molecule and the oxygen atom of another water molecule.

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44
Q

what is the strength of hydrogen bonds?

A

Individually they are weak but because there are so many of them within water make the structure of water very strong.

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45
Q

what does water to water form?
why

A

A cohesive force
strong attraction due to hydrogen bonding.

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46
Q

what does water to a polar ion form?

A

creates an adhesive force.

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47
Q

what do forces of cohesion and adhesion help?

(in a plant)

A
  • forces of cohesion and adhesion help water travel up the xylem vessel of the stem of plants.
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48
Q

what do water droplets form?
what causes this

A

form spheres
(cohesion between water molecules)

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49
Q

what causes high surface tension in water?

A

due to cohesion forces (hydrogen bonds) which also causes the ‘skin’ where the water meets the air.

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50
Q

what can the surface of the water behave like?
what do molecules on the surface do?

A

Behave like an elastic sheet due to cohesion.
they pull strongly together as they are not affected by the molecules above them.

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51
Q

What is the importance of water having a high surface tension?

A
  • some animals (pond skaters) can walk on water.
  • A habitat can be produced on top of the water
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52
Q

what is the property of latent heat?

why does this happen

A

a great deal of heat energy is needed to change water from a liquid to a vapour. because there are many hydrogen bonds.

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53
Q

what is needed to break hydrogen bonds?

A

Lots of energy

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54
Q

what does water have in terms of latent heat?

A

high latent heat of evaporation so when changing from water to vapour it absorbs a large amount of heat energy.

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55
Q

what is the importance/function of having high latent heat?

A

The evaporation of water (sweating) takes away energy from the skin and causes the cooling effect.

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56
Q

why does water have high specific heat capacity?

A

because there are many hydrogen bonds, a large amount of heat energy is needed to raise the temperature of water.

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57
Q

what is the importance/function of water having a high specific heat capacity?
(internal temperature)

A

allows the cell to maintain a relatively stable internal temperature & stops enzymes denaturing because a large amount of heat energy is needed to raise a cells temperature.

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58
Q

what is the importance/function of water having a high specific heat capacity?
(environmental temperature)

A

prevents fluctuation in the water temperature. provides a thermostatically stable environment for aquatic organisms

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59
Q

When is water used as a reactant?

A

In photosynthesis and hydrolysis reactions

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60
Q

what is a hydrolysis reaction?

A

the insertion of water

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61
Q

what is a condensation reaction?

A

the removal of water

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62
Q

why is water a universal solvent?

A

because it is polar

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63
Q

what does it mean in terms of water being a universal solvent?

A

-dissolves lots of different solutes
-effect solvent as it can form hydrogen bonds with ions (NaCl)

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64
Q

what does the positive end of the water molecule attract?

A

negative ion

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65
Q

what does the negative end of the water molecule attract?

A

positive ion

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66
Q

what do water molecules do?
(ions)

A

they surround ions and then they dissolve

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67
Q

what is the importance/function of water being a universal solvent?

A
  • chemical reactions can happen
  • makes transport inside living things easier
  • act as a transport medium carrying dissolved molecules
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68
Q

what are some examples of dissolved molecules in water?
(animals/plants)

A
  • blood in animals
  • water transports minerals ions in the xylem
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69
Q

what is denser, ice or water?

A

ice is less dense than water so will float on top.

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70
Q

why is water less dense when frozen?

A

Because the distance between water molecules increases. held in a lattice structure with hydrogen bonds.

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71
Q

what is the difference between ice and water in terms of density?

A

water- molecules are closer, higher density
ice- water molecules are much more spread out, lattice, lower density

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72
Q

what is the importance/function of the density of water?

A

ice forms an insulating layer in top of water which prevents it all from freezing. the liquid beneath the ice has a higher temperature than the air above it.

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73
Q

what does the density of water mean for the living organisms?

A

organisms living in a pond that is covered in ice will still survive. They won’t freeze

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74
Q

what is the colour of water?

A

colourless which makes it transparent to light

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75
Q

what is the importance of water being colourless?

A

sunlight can reach plants at the bottom of the water. photosynthesis can occur

76
Q

why is phosphorus required?

A

to synthesise phospholipids/nucleotides/ ATP/DNA/RNA

77
Q

why is sulphur required?

A

to synthesise some amino acids/ methionine/ cysteine/ proteins

78
Q

water is metabolite, what does this mean?

A

metabolite is a molecule that takes part in metabolic reactions. this is a biochemical reaction that takes place inside cells in order to keep them alive.

79
Q

when is water a key metabolite>

A

in condensation and hydrolysis reactions.

80
Q

what do carbohydrates contain?

A

carbon, hydrogen, oxygen

81
Q

are they organic ?

A

yes because there are more than one carbon

82
Q

what are carbohydrates made up of?

A

chains of individual monomer components joined together to form a polymer.

83
Q

what is a monomer?

A

single repeating units of a polymer

84
Q

what is carbohydrates monomer?

A

monosaccharide

85
Q

2 monosaccharides ?

A

disaccharides

86
Q

3 or more monosaccharides?

A

polysaccharides

87
Q

properties of monosaccharides?

A

-sweet
- organic
- soluble molecules
-building blocks for other larger carbohydrate

88
Q

what’s the general formula of monosaccharides?

A

(CH20)n

89
Q

how many carbon atoms do the following have?
TRIOSE/PENTOSE/HEXOSE

A
  • three
  • five
  • six
90
Q

function of triose?
example of one…..

A

important in metabolism. triose sugars are intermediate in the reactions of respiration and Photosynthesis
(glyceraldehyde)

91
Q

function of pentose
example…..

A

molecules of nucleic acids such as DNA,RNA,ATP
(ribose/deoxyribose)

92
Q

function of hexose
example…

A

(glucose) it is a source of energy in respiration. C-H and C-C bonds are broken to release energy. this energy is transferred to make adenosine triphosphate (ATP)

93
Q

what is an isomer?

A

they have the same chemical formula and the same number of atoms but the atoms are arranged differently.

94
Q

what are the isomers of glucose?
how do you know which is which

A

alpha(H above/ OH below) and beta (H below/ OH above)

95
Q

which glucose can be broken down in respiration?

A

only alpha glucose because only enzymes which git its shape are present.

96
Q

condensation reaction?

A

removing water, formation of glycosidic bond by the removal of water

97
Q

hydrolysis reaction?

A

breaking of glycosidic bond by the addition of water.

98
Q

what’s a disaccharide?

A

two monosaccharides bonded with the formation of a glycosidic bond and the removal of water

99
Q

explain the formation of a hexose disaccharide

A

-glycosidic bonds between carbon one on one monosaccharides and carbon four on another
-the hydroxyl group (-OH) on each monosaccharide aligns
-each glycosidic bond = one molecule of water removed
-oxygen atom left to join the two monosaccharides together
-1-4 Glycosidic bond is formed

100
Q

what are the monomers in maltose?
what’s the use for it in living organisms?

A

alpha glucose + alpha glucose
found in germinating seeds

101
Q

what are the monomers in sucrose?
use in living organisms

A

alpha glucose + fructose
A product of photosynthesis which is transported into the phloem

102
Q

What are the monomers in lactose?
use in living organisms

A

alpha glucose + galactose
Found in mammals milk

103
Q

What is a reducing sugar

A

A reducing sugar is a sugar that can donate an electron to another chemical

104
Q

examples of reducing sugar

A

-all monosaccharides (glucose/fructose/galactose)
- some disaccharides maltose
- Not sucrose

105
Q

Reducing sugar test

A

-Add Benedicts reagent to the sample HEAT
-if reducing sugar is present colour change from blue to brick red
-if the reducing sugar is not present the colour remains blue

106
Q

Why is the Benedict’s test semi quantitive method

A

Because it indicates presence or absence of glucose as well as the relative concentration of different solutions however you can’t give it a value

107
Q

How do you test a non-reducing sugar

A

It must be broken down into its monosaccharide components by hydrolysis (can then be tested as a reducing sugar)

108
Q

Non-reducing sugar test

A

-Add Benedict’s, heat
-if colour is blue add hydrochloric acid and heat to hydrolyse glycosidic bonds
-add sodium hydroxide to neutralise solution (test with litmus paper)
-add Benedict’s, heat
- if a non-reducing sugar is present blue to brick red
- if a non-reducing sugar is not present, colour will remain blue

109
Q

What does a biosensor do

A

Gives an accurate measurement of sugar present

110
Q

what’s a polysaccharide?

A

polymers of many monosaccharides all joined by condensation reactions, via glycosidic bonds.

111
Q

what’s the general formula of a polysaccharide?

A

(C6H10O5)n

112
Q

what is polymerisation?

A

process of bonding many monomers by condensation reactions to form one large molecule

113
Q

general properties of polysaccharides?

A

-often folded/can be branched
- are not sugar
- not sweet, cannot be crystalised
-insoluble
- compact molecules
- carry lots of energy

113
Q

polysaccharide property
(glucose)

how is water drawn into the cell avoided?

A

-is the main source of energy in a cell and has to be store (cannot be left as a monosaccharide)
-soluble in water, would increase the concentration of the cell so would draw water into the cell by osmosis.
- glucose is converted into a storage product (polysaccharide)

114
Q

why is it important that polysaccharides are insoluble?

A

means the cell is osmotically stable.
stops the cell from bursting

115
Q

why can’t polysaccharides difuse out of cells?

A

they’re too big

116
Q

what are the storage polysaccharides?

A

starch/glycogen

117
Q

structure polysaccharides?

A

cellulose/chitin

118
Q

what is starch?

A

-a storage polysaccharide
-found in plants as small grains/seeds
- energy source in plants

119
Q

function of starch?

A

main source of glucose in plants

120
Q

structure of starch?

A

mixture of 2 polymers (a glucose monosaccharides)

121
Q

bonded together in 2 different ways forms…..
(starch)

A

amylose and amylopectin

122
Q

amylose propeties

A
  • long linear
  • unbranched chain of a glucose
  • coiled shape wound tight into a coil (v good energy store)
  • 1-4 glycosidic bonds
123
Q

why is amylose not very good for releasing energy?

A

as it only has 2 ends where the reactions can happen for energy to be released

124
Q

amylopectin properties

A

-long branched chain of a glucose
- 1-4/1-6 glycosidic bonds formed by condensation reactions

125
Q

why can glucose be released quickly in amylopectin

A

because it’s branched so lots of ends where glucose can be released from

126
Q

what are the characteristics that make starch a good energy store

A

-insoluble and so don’t draw water into/ or out of the cell by osmosis
- compact
- when hydrolysed, forms monosaccharides of alpha glucose, easily transported/used in respiration

127
Q

important properties of starch
(3)

A
  • insoluble in water
  • osmotically stable
  • good energy store
128
Q

is the starch test quantitive/ qualative?

A

qualative

129
Q

explain the starch test…

A
  • Add iodine
  • if starch is present, colour change from brown-black
  • if starch isn’t present, colour will remain the same
130
Q

what is glycogen?

A

main storage product in animal, looks like amylopectin (highly branched)

131
Q

where is glycogen stored?

A

stored in the liver/ skeletal muscle

132
Q

what’s the difference between glycogen and amylopectin?

A

more side branches, means stored glucose can be released quickly

133
Q

what are the bonds in glycogen>

A

1-4 glycosidic

134
Q

what does glycogen being highly branched mean?

A

means it’s easier to hydrolyse glycosidic bonds and releases glucose.
very good for energy release

135
Q

where is cellulose found?

A

found in plant cellulose cell walls

136
Q

what is cellulose made up of?

A

Made up of repeating units of B glucose
held by 1-4 glycosidic bonds
every other B glucose rotates 180 degrees so that OH line up so H2O can be removed and glycosidic bonds form

137
Q

what does cellulose rotating 180 degrees allow?

A

allows hydrogen bonds to form between chains of beta glucose (cross links)

138
Q

what do lots of chains of cellulose joined together form

A

microfibrils

139
Q

explain structure of cellulose in terms of bonds etc..

A
  • hydrogen bonds between the chains
  • makes cellulose strong
  • important for cell wall structure
  • stops plant cells from bursting when water enters
140
Q

what is chitin?

A

similar to cellulose but for animals

141
Q

what does chitin form?

A

forms the exoskeletons of insects and fungi cell walls

142
Q

properties of chitin

A
  • strong
  • lightweight
  • waterproof
143
Q

what happens that’s difference than cellulose

A

some OH groups are replaced by nitrogen containing acetylamine groups
- monomers in each chains are rotated 180
- h bonds form between chains of chitin (cross links)
- forms microfibrils

144
Q

what makes cellulose strong

A

the numerous hydrogen bonds

145
Q

most common type of lipid

A

triglycerides

146
Q

how are triglycerides formed

A

by 3 condensation reaction between glycerol and fatty acids.

147
Q

structure of a triglyceride

A

3 fatty acids
1 glycerol
insoluble
form an ester bonds

148
Q

how can triglycerides differ

A

length of the fatty acid chain (no of carbons)\
whether they’re saturated/ unsaturated

149
Q

what is atherosclerosis

A

heart disease caused by fatty deposits (atheroma) in the coronary arteries

150
Q

explain what saturated fats contain and what they do

A

they contain low density lipoproteins
these build up and restrict blood flow

151
Q

explain what unsaturated fatty acids contain and what they do

A

make more high density lipoprotein
these are good because they carry LDLs to the liver for disposal

152
Q

uses of triglycerides
(when oxidised)

A
  • triglycerides release more energy for use in respiration than an equal mass of carbohydrate lipids
153
Q

other uses of triglycerides

A

-protection around important organs
- produce lots of metabolic water when oxidised (important for camels)
- stored under skin/ important for insulation
- component of cell membrane
- waterproofing

154
Q

what’s an ester bond

A

an oxygen atom joining two atoms, one of which Is a carbon atom attached by a double bonds to another oxygen atom

155
Q

what do lipoproteins travel around the body in

A

the bloodstream

156
Q

atherosclerosis
=?

A

disease

157
Q

atheroma
=?

A

fatty deposits

158
Q

what makes a phospholipid different to a triglyceride

A

one of the fatty acid molecules is replaced by a phosphate group

159
Q

explain the structure of a phospholipid

A

phosphate head which is hydrophilic
and a fatty acid tail which is hydrophobic

160
Q

adaptation of a phospholipid

A

the phospholipid bilayer

161
Q

where are phospholipids found

A

found in cell membranes

162
Q

what is the non protein part of haemoglobin contain

A

a ham group which contains iron

163
Q

what is glucose

A

the main energy source for most cell
main form in which carbohydrates are transported around the body of animals

164
Q

function of monosaccharides

A
  • a source of energy in respiration
  • building blocks for large molecules
  • intermediate in reactions
  • used to make nucleotides
165
Q

lipids in terms of water

A

they are insoluble in water but soluble in organic solvents such as ethanol

166
Q

what are the chemical properties of lipids

A

non-polar molecules
insoluble in water but dissolve in organic solvents
fats are solid at room temp whereas oils are liquid

167
Q

what are waxes

A

similar to fats and oils but also contain alcohol
they’re insoluble and are important in organisms such as insects where the waxy cuticle cuts down water loss and to reduce transpiration

168
Q

what is the emulsion test for lipids

A

ethanol is added to the sample, test tube is shaken.
if a lipids is present the solution will go to a milky white precipitate

169
Q

what bonds are in proteins

A

hydrogen
disulphide
ionic
hydrophobic/hydrophillic interactions

170
Q

four protein structures

A

primary
secondary
tertiary
quaternary

171
Q

definition of primary structure

A

sequence of amino acids in a polypeptide
only link by peptide bonds

172
Q

what is the secondary structure

A

shape that the polypeptide chain forms as a result of hydrogen bonding.
alpha helix (helical/spiral)
b pelted sheets (flat sheets/ zig zag shape)

173
Q

tertiary structure

A

formed by the bending and twisting of the polypeptide helix into a compacted structure. this gives the molecules its 3D shape.
shape is maintained by disulphide, ionic and H bonds

174
Q

quaternary structure

A

combination of 2 or more polypeptide chains in tertiary form
larger more complex molecules

175
Q

example of a globular protein

A

haemoglobin

176
Q

function of globular protein

A

enzymes
antibodies
plasma proteins
hormones

177
Q

globular proteins

A

spherical molecules
soluble in water

178
Q

explain how globular proteins are structured

A

bended and twisted so the hydrophobic molecules are in the middle, hydrophilic on the outside

179
Q

example of a fibrous protein

A

collagen

180
Q

fibrous protein

A

perform structural functions
secondary structure
consists of polypeptides in parallel chains/sheets with numerous cross linkages to form fibres (keratin in hair)
insoluble in water, strong and tough

181
Q

what does collagen do

A

provides tough properties needed in tendons. a single fibre consists of 3 polypeptide chains twisted around each other like a rope

182
Q

test for proteins

A
  • add Biuret Reagant and blue coupe (II) sulphate and sodium hydroxide to the solution
    shake it
183
Q

what is the result of the protein test

A

solution will turn purple in the presence of peptide bonds (protein)

184
Q

more purple solution

A

more peptide bonds

Biology (12 decks)

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