Brainscape's Knowledge GenomeTM

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


See full index

Biology A Level > 1 - Biological Molecules > Flashcards

1 - Biological Molecules Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Structure of an amino acid

A

Check

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

What is an amine group?

A

The H-N-H part

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

What is a carboxyl group?

A

The O=C-OH part

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

How does an amino acid become polar?

A

The OH on the carboxyl group dissociates and joins the H-N-H on the amine group, forming ammonia which is positive. This also leaves a negative charge on the carboxyl group

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

What reaction breaks up 2 amino acids?

A

Hydrolysis, requiring H2O

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

What reaction joins up 2 amino acids?

A

Condensation, releasing H2O

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

What is the bond between two amino acids called?

A

peptide

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

What is the test for proteins?

A

Biuret test

  • crushed in distilled water and filter
  • add NaOH and 1% CuSO4
  • light blue to lilac
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which forces join up proteins and what are they between?

A

Disulfide bridges - S and S
Ionic bonds - oppositeley charged stuff
Hydrogen bonds - H and O/N
London forces - everything

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

How do you break each of these bonds?

A

Hydrogen - heat
Ionic - change in pH
Disulfide - reducing agent
London - heat

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

order the bonds by strength high to low

A

Disulfide
Ionic
Hydrogen
London

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

what is primary structure?

A

the sequence of amino acids in a chain.

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

what is secondary structure?

A

the 3-D shape of the protein. Can either be a beta-pleated sheet or alpha helix

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

what is tertiary structure?

A

the overall 3-D shape, e.g fibrous or globular

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

which structure is disrupted by breaking one of the intermolecular forces?

A

tertiary

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

what is the induced fit theory?

A

as the substrate comes close to the active site, it forms bonds that change its tertiary structure. This causes a strain on the bonds of the substrate, making them easier to break.

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

what factors affect the rate of an enzyme-controlled reaction?

A
  • enzyme concentration
  • substrate concentration
  • pH
  • temperature
  • competitive and non-competitive inhibitors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is ATP made of?

A

one adenine molecule, connected to a ribose sugar, connected to 3 phosphate groups

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

compare the structure of atp with a nucleotide

A
  • atp always has adenine, nucleotide can have any base including adenine
  • atp has ribose sugar, nucleotide has any deoxyribose sugar
  • atp has 3 phosphate groups, nucleotides have one
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what happens to atp to release energy?

A

atp gets hydrolysed, as the covalent bond between the second and third phosphate groups is very unstable

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

what enzyme hydrolyses atp?

A

atp hydrolase

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

what is produced when atp is hydrolysed?

A

adenine diphosphate (adp) and a phosphate

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

what is required for the hydrolysis of atp?

A

water

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

how can adp be converted back to atp and what is required?

A

condensation reaction, requires:

  • adp
  • phosphate group
  • atp synthase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

when is atp synthesised?

A

photosynthesis or respiration

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

what can the inorganic phosphate group that is released be used for?

A

phosphorylate other compounds, making them more reactive

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

what is a monosaccharide

A

the monomers from which larger carbohydrates can be made

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

name three monosaccharides

A
  • glucose
  • galactose
  • fructose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

draw alpha glucose

A

check

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

draw beta glucose

A

check

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

what is the difference between alpha glucose and beta glucose?

A
  • in alpha glucose, on the right the H is on the top and the OH is on the bottom
  • in beta glucose, on the right the OH is on the top and the H is on the bottom
32
Q

what reaction joins two monosaccharides into a disaccharide?

A

condensation reaction that releases water

33
Q

what bond is formed between two monosaccharides in a disaccharide?

A

glycosidic

34
Q

what is maltose made from?

A

glucose and glucose

35
Q

what is sucrose made from?

A

glucose and fructose

36
Q

what is lactose made from?

A

glucose and galactose

37
Q

what is a polysaccharide?

A

lots of monosaccharides

38
Q

what are the two polysaccharides made from alpha glucose?

A
  • glycogen

- starch

39
Q

compare starch and cellulose

A
  • starch made of alpha glucose, cellulose made of beta glucose
  • inverted shape, position of hydrogen and hydroxyl groups on carbon 1 inverted
40
Q

why are the sugars called “reducing sugars”?

A

an OH group makes it reducing, so when they become disaccharides the OH group becomes an O, except for in maltose

41
Q

general structure of glycogen

A
  • forms 1-4 glycosidic bonds and 1-6 bonds where it branches out
  • spherical, densely packed
42
Q

general structure of amylose starch

A
  • linear unbranched polymer with 1-4 glycosidic bonds

- coils into an alpha helix, held together by hydrogen bonds

43
Q

general structure of amylopectin starch

A
  • linear, branched polymer with parallel chains with 1-6 glycosidic bonds
  • forms parallel chains
44
Q

why does starch need to be insoluble?

A

otherwise would decrease the water potential inside the cell, so water would move in and the cell would become turgid and lyse

45
Q

why do we need amylopectin and glycogen?

A

amylase can only hydrolyse the terminal glucose, so if there are more branches more terminal glucoses can be hydrolysed at the same time. faster energy release

46
Q

general structure of cellulose

A

chains that run parallel with hydrogen bonds between them. these form microfibrils which join together to make macrofibrils.

47
Q

how is cellulose’s structure good for its function?

A

microfibrils and macrofibrils are very strong, and make fibres which make good cell walls

48
Q

test for reducing sugars

A

Benedict’s solution goes from blue to brick red in a reducing sugar

49
Q

test for starch

A

iodine goes from orange to blue/black

50
Q

what is a competitive inhibitor?

A

an inhibitor that is the same shape as the substrate.

51
Q

graph for competitive inhibitor

A

check

52
Q

what is a non-competitive inhibitor?

A

forms intermolecular forces with the allosteric site which changes the shape of the active site meaning the substrate no longer binds.

53
Q

graph for non-competitive inhibitor

A

check

54
Q

how is a triglyceride formed

A

when each hydroxyl group on the glycerol combines with a carboxyl group on the fatty acid. this is a condensation reaction which releases 3 H2O molecules

55
Q

what bond is formed between the glyceride and three fatty acids

A

ester bond

56
Q

saturated fats

A
  • single bonds
  • straight so can be packed together
  • solids at room temperature
57
Q

unsaturated fats

A
  • at least one double bond
  • kinky chain so don’t pack closely
  • oils at room temperature
58
Q

what is a phospholipid compared to a triglyceride?

A

one of the fatty acids is replaced with a phosphate sugar

59
Q

which part of a p.lipid is hydrophobic and which part is hydrophilic?

A
  • fatty acids are hydrophobic

- polar glycerol phosphate group is hydrophilic

60
Q

test for fats

A
  • emulsion test

- add ethanol, if present emulsion will happen where droplets will be suspended

61
Q

name the 4 important properties of water

A
  • cohesion and surface tension
  • metabolite
  • solvent
  • high specific heat capacity
62
Q

use of hydrogen ions

A

regulating pH

63
Q

use of iron ions

A

haemoglobin

64
Q

use of sodium ions

A

co-transport of glucose and amino acids

65
Q

use of phosphate ions

A

DNA and ATP

66
Q

function of DNA

A

carry genetic information

67
Q

function of RNA

A

transferring genetic information from DNA to ribosomes

68
Q

what makes up a nucleotide

A

pentose sugar-phosphate backbone with a nitrogen containing organic base

69
Q

what bond joins up two nucleotides

A

phosphodiester bond

70
Q

compare RNA and DNA

A
  • both have phosphate group
  • DNA has deoxyribose, RNA has ribose
  • DNA has a,c,t or g, RNA has a,c,g or uracil
  • DNA is double helix, RNA is single chain
  • DNA is pretty long, RNA is pretty short
71
Q

what are ribosomes made of

A

RNA and proteins

72
Q

How does the Benedict test work?

A

It contains copper sulfate (hence the blue colour)
Reducing sugars contain an aldehyde group or a ketone group
These reduce Cu2+ ions to Cu+ ions, forming the brick red copper oxide precipitate

73
Q

what is the difference between secondary structure and tertiary structure?

A

secondary structure is forces between the amine group of one amino acid and the carboxyl group of another.
tertiary structure is forces between the R groups of amino acids

74
Q

properties of fibrous proteins

A
  • parallel polypeptide chains crosslinked
  • form long fibres or sheets
  • usually insoluble in water
  • physically tough
  • eg collagen, silk and keratin
75
Q

properties of globular proteins

A
  • tightly folded polypeptide chains
  • form spherical shape
  • usually soluble, as hydrophobic groups on the inside and hydrophilic groups on the outside
  • eg enzymes, antibodies and many hormones
76
Q

what is quaternary structure

A

arrangement of different polypeptide chains and prosthetic groups within a protein

77
Q

what is a prosthetic group

A

a non amino acid part of a conjugated protein

Biology A Level (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions