1.6: Proteins Flashcards
1
Q
Proteins are usually what molecules?
A
Proteins are usually very large molecules
2
Q
Proteins are usually very large molecules.
The types of carbohydrates and lipids in all organisms are what?
A
The types of carbohydrates and lipids in all organisms are:
- Relatively few
- Very similar
3
Q
Proteins are usually very large molecules.
The types of carbohydrates and lipids in all organisms are relatively few and they are very similar.
However, each organism has numerous proteins that do what?
A
Each organism has numerous proteins that differ from:
- Species
to
- Species
4
Q
Proteins are usually very large molecules.
The types of carbohydrates and lipids in all organisms are relatively few and they are very similar.
However, each organism has numerous proteins that differ from species to species.
The shape of any one type of protein molecule differs from what?
A
The shape of any one type of protein molecule differs from that of all other types of proteins
5
Q
Proteins are usually very large molecules.
The types of carbohydrates and lipids in all organisms are relatively few and they are very similar.
However, each organism has numerous proteins that differ from species to species.
The shape of any one type of protein molecule differs from that of all other types of proteins.
Proteins are very important molecules in living organisms.
Indeed the word ‘protein’ is a Greek work meaning what?
A
Indeed the word ‘protein’ is a Greek work meaning ‘of first importance’
6
Q
Proteins are usually very large molecules.
The types of carbohydrates and lipids in all organisms are relatively few and they are very similar.
However, each organism has numerous proteins that differ from species to species.
The shape of any one type of protein molecule differs from that of all other types of proteins.
Proteins are very important molecules in living organisms.
Indeed the word ‘protein’ is a Greek work meaning ‘of first importance.’
One group of proteins, what, is involved in almost every what?
A
One group of proteins, enzymes, is involved in almost every living process
7
Q
Proteins are usually very large molecules.
The types of carbohydrates and lipids in all organisms are relatively few and they are very similar.
However, each organism has numerous proteins that differ from species to species.
The shape of any one type of protein molecule differs from that of all other types of proteins.
Proteins are very important molecules in living organisms.
Indeed the word ‘protein’ is a Greek work meaning ‘of first importance.’
One group of proteins, enzymes, is involved in almost every living process.
There is a vast range of different enzymes that between them do what?
A
There is a vast range of different enzymes that between them perform a very diverse number of functions
8
Q
The structure of an amino acid:
What are amino acids?
A
Amino acids are the basic monomer units that combine to make up a polymer called a polypeptide
9
Q
The structure of an amino acid:
Amino acids are the basic monomer units that combine to make up a polymer called a polypeptide.
Polypeptides can be combined to do what?
A
Polypeptides can be combined to form proteins
10
Q
The structure of an amino acid:
Amino acids are the basic monomer units that combine to make up a polymer called a polypeptide.
Polypeptides can be combined to form proteins.
How many amino acids have been identified?
A
About 100 amino acids have been identified
11
Q
The structure of an amino acid:
Amino acids are the basic monomer units that combine to make up a polymer called a polypeptide.
Polypeptides can be combined to form proteins.
About 100 amino acids have been identified, of which how many occur naturally where?
A
About 100 amino acids have been identified, of which 20 occur naturally in proteins
12
Q
The structure of an amino acid:
Amino acids are the basic monomer units that combine to make up a polymer called a polypeptide.
Polypeptides can be combined to form proteins.
About 100 amino acids have been identified, of which 20 occur naturally in proteins.
The fact that the same 20 amino acids occur in all living organisms provides what?
A
The fact that the same 20 amino acids occur in all living organisms provides indirect evidence for evolution
13
Q
The structure of an amino acid:
Every amino acid has a what?
A
Every amino acid has a central carbon atom
14
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached what?
A
Every amino acid has a central carbon atom to which are attached 4 different chemical groups:
- The amino group
- The carboxyl group
- A hydrogen atom
- R (side) group
15
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached 4 different chemical groups - the amino group, the carboxyl group, a hydrogen atom and the R (side) group.
The amino group is -what?
A
The amino group is -NH2
16
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached 4 different chemical groups - the amino group, the carboxyl group, a hydrogen atom and the R (side) group.
The amino group is -NH2.
The amino group is a basic group from which what is derived?
A
The amino group is a basic group from which the ‘amino’ part of the name amino acid is derived
17
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached 4 different chemical groups - the amino group, the carboxyl group, a hydrogen atom and the R (side) group.
The carboxyl group is -what?
A
The carboxyl group is -COOH
18
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached 4 different chemical groups - the amino group, the carboxyl group, a hydrogen atom and the R (side) group.
The carboxyl group is -COOH.
The carboxyl group is a what group which gives what?
A
The carboxyl group is an acidic group which gives the amino acid the ‘acid’ part of its name
19
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached 4 different chemical groups - the amino group, the carboxyl group, a hydrogen atom and the R (side) group.
The hydrogen atom is -what?
A
The hydrogen atom is -H
20
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached 4 different chemical groups - the amino group, the carboxyl group, a hydrogen atom and the R (side) group.
What is the R (side) group?
A
The R (side) group is a variety of different chemical groups
21
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached 4 different chemical groups - the amino group, the carboxyl group, a hydrogen atom and the R (side) group.
The R (side) group is a variety of different chemical groups.
Each amino acid has a different what?
A
Each amino acid has a different R group
22
Q
The structure of an amino acid:
Every amino acid has a central carbon atom to which are attached 4 different chemical groups - the amino group, the carboxyl group, a hydrogen atom and the R (side) group.
The R (side) group is a variety of different chemical groups.
Each amino acid has a different R group.
The 20 naturally occurring amino acids differ only in their what?
A
The 20 naturally occurring amino acids differ only in their R (side) group
23
Q
The formation of a peptide bond:
In a similar way that monosaccharide monomers combine to form disaccharides, amino acid monomers can combine to form what?
A
In a similar way that monosaccharide monomers combine to form disaccharides:
- Amino acid monomers
can combine to form
- A dipeptide
24
Q
The formation of a peptide bond:
In a similar way that monosaccharide monomers combine to form disaccharides, amino acid monomers can combine to form a dipeptide.
The process is essentially the same - the what in a what reaction?
A
The process is essentially the same - the removal of a water molecule in a condensation reaction
25
The formation of a peptide bond:
In a similar way that monosaccharide monomers combine to form disaccharides, amino acid monomers can combine to form a dipeptide.
The process is essentially the same - the removal of a water molecule in a condensation reaction.
The water is made by doing what?
The water is made by combining a:
1. -OH from the carboxyl group of one amino acid
with
2. -H from the amino group of another amino acid
26
The formation of a peptide bond:
In a similar way that monosaccharide monomers combine to form disaccharides, amino acid monomers can combine to form a dipeptide.
The process is essentially the same - the removal of a water molecule in a condensation reaction.
The water is made by combining a -OH from the carboxyl group of one amino acid with a -H from the amino group of another amino acid.
The 2 amino acids then become what?
The 2 amino acids then become linked
27
The formation of a peptide bond:
In a similar way that monosaccharide monomers combine to form disaccharides, amino acid monomers can combine to form a dipeptide.
The process is essentially the same - the removal of a water molecule in a condensation reaction.
The water is made by combining a -OH from the carboxyl group of one amino acid with a -H from the amino group of another amino acid.
The 2 amino acids then become linked by what?
The 2 amino acids then become linked by a new peptide bond
28
The formation of a peptide bond:
In a similar way that monosaccharide monomers combine to form disaccharides, amino acid monomers can combine to form a dipeptide.
The process is essentially the same - the removal of a water molecule in a condensation reaction.
The water is made by combining a -OH from the carboxyl group of one amino acid with a -H from the amino group of another amino acid.
The 2 amino acids then become linked by a new peptide bond between what?
The 2 amino acids then become linked by a new peptide bond between the:
1. Carbon atom of one amino acid
2. Nitrogen atom of the other
29
The formation of a peptide bond:
In a similar way that monosaccharide monomers combine to form disaccharides, amino acid monomers can combine to form a dipeptide.
The process is essentially the same - the removal of a water molecule in a condensation reaction.
The water is made by combining a -OH from the carboxyl group of one amino acid with a -H from the amino group of another amino acid.
The 2 amino acids then become linked by a new peptide bond between the carbon atom of one amino acid and the nitrogen atom of the other.
In a similar way as a glycosidic bond of a disaccharide can be broken by the addition of water (hydrolysis), the peptide bond of a dipeptide can also be broken by what?
In a similar way as a glycosidic bond of a disaccharide can be broken by the addition of water (hydrolysis), the peptide bond of a dipeptide can also be broken by hydrolysis
30
The formation of a peptide bond:
In a similar way that monosaccharide monomers combine to form disaccharides, amino acid monomers can combine to form a dipeptide.
The process is essentially the same - the removal of a water molecule in a condensation reaction.
The water is made by combining a -OH from the carboxyl group of one amino acid with a -H from the amino group of another amino acid.
The 2 amino acids then become linked by a new peptide bond between the carbon atom of one amino acid and the nitrogen atom of the other.
In a similar way as a glycosidic bond of a disaccharide can be broken by the addition of water (hydrolysis), the peptide bond of a dipeptide can also be broken by hydrolysis to give what?
In a similar way as a glycosidic bond of a disaccharide can be broken by the addition of water (hydrolysis), the peptide bond of a dipeptide can also be broken by hydrolysis to give its 2 constituent amino acids
31
The primary structure of proteins - polypeptides:
Through a series of what, many amino acid monomers can be joined together in a process called what?
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation
32
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
What is a polypeptide?
A polypeptide is the resulting chain of many hundreds of amino acids
33
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
What forms the primary structure of any protein?
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein
34
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein.
This sequence is determined by what?
This sequence of amino acids in a polypeptide chain is determined by DNA
35
Polypeptides have many (usually how many) of the what joined in different sequences?
Polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences
36
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein.
This sequence is determined by DNA.
As polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences, it follows that there is an almost limitless number of possible what?
As polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences, it follows that there is an almost limitless number of possible:
1. Combinations
2. Therefore types of primary protein structure
37
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein.
This sequence is determined by DNA.
As polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences, it follows that there is an almost limitless number of possible combinations and therefore types of primary protein structure.
It is the primary structure of a protein that determines its what?
It is the primary structure of a protein that determines its:
1. Shape
2. Therefore its function
38
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein.
This sequence is determined by DNA.
As polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences, it follows that there is an almost limitless number of possible combinations and therefore types of primary protein structure.
It is the primary structure of a protein that determines its shape and therefore its function.
A change in just what can lead to a change in what?
A change in just a single amino acid in this primary sequence can lead to a change in the shape of the protein
39
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein.
This sequence is determined by DNA.
As polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences, it follows that there is an almost limitless number of possible combinations and therefore types of primary protein structure.
It is the primary structure of a protein that determines its shape and therefore its function.
A change in just a single amino acid in this primary sequence can lead to a change in the shape of the protein and may stop what?
A change in just a single amino acid in this primary sequence:
1. Can lead to a change in the shape of the protein
2. May stop it carrying out its function
40
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein.
This sequence is determined by DNA.
As polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences, it follows that there is an almost limitless number of possible combinations and therefore types of primary protein structure.
It is the primary structure of a protein that determines its shape and therefore its function.
A change in just a single amino acid in this primary sequence can lead to a change in the shape of the protein and may stop it carrying out its function.
Change its shape and it will do what?
Change its shape and it will function:
1. Less well
Or,
2. Differently
41
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein.
This sequence is determined by DNA.
As polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences, it follows that there is an almost limitless number of possible combinations and therefore types of primary protein structure.
It is the primary structure of a protein that determines its shape and therefore its function.
A change in just a single amino acid in this primary sequence can lead to a change in the shape of the protein and may stop it carrying out its function.
Change its shape and it will function less well or differently.
A simple protein may consist of what?
A simple protein may consist of a single polypeptide chain
42
The primary structure of proteins - polypeptides:
Through a series of condensation reactions, many amino acid monomers can be joined together in a process called polymerisation.
A polypeptide is the resulting chain of many hundreds of amino acids.
The sequence of amino acids in a polypeptide chain forms the primary structure of any protein.
This sequence is determined by DNA.
As polypeptides have many (usually hundreds) of the 20 naturally occurring amino acids joined in different sequences, it follows that there is an almost limitless number of possible combinations and therefore types of primary protein structure.
It is the primary structure of a protein that determines its shape and therefore its function.
A change in just a single amino acid in this primary sequence can lead to a change in the shape of the protein and may stop it carrying out its function.
Change its shape and it will function less well or differently.
A simple protein may consist of a single polypeptide chain.
More commonly, however, a protein is made up of what?
More commonly, however, a protein is made up of a number of polypeptide chains
43
The secondary structure of proteins:
The linked amino acids that make up a polypeptide possess both what groups?
The linked amino acids that make up a polypeptide possess both:
1. -NH
2. -C = O
groups
44
The secondary structure of proteins:
The linked amino acids that make up a polypeptide possess both -NH and -C = O groups where?
The linked amino acids that make up a polypeptide possess both:
1. -NH
2. -C = O
groups on either side of every peptide bond
45
The secondary structure of proteins:
The linked amino acids that make up a polypeptide possess both -NH and -C = O groups on either side of every peptide bond.
What has an overall positive charge?
The H of the -NH group has an overall positive charge
46
The secondary structure of proteins:
The linked amino acids that make up a polypeptide possess both -NH and -C = O groups on either side of every peptide bond.
The H of the -NH group has an overall positive charge, while what has overall negative charge?
The:
1. H of the -NH group has an overall positive charge
,while
2. O of the -C = O group has an overall negative charge
47
The secondary structure of proteins:
The linked amino acids that make up a polypeptide possess both -NH and -C = O groups on either side of every peptide bond.
The H of the -NH group has an overall positive charge, while the O of the -C = O group has an overall negative charge.
These 2 groups therefore do what?
These 2 groups therefore readily form weak bonds
48
The secondary structure of proteins:
The linked amino acids that make up a polypeptide possess both -NH and -C = O groups on either side of every peptide bond.
The H of the -NH group has an overall positive charge, while the O of the -C = O group has an overall negative charge.
These 2 groups therefore readily form weak bonds, called what?
These 2 groups therefore readily form weak bonds, called hydrogen bonds
49
The secondary structure of proteins:
The linked amino acids that make up a polypeptide possess both -NH and -C = O groups on either side of every peptide bond.
The H of the -NH group has an overall positive charge, while the O of the -C = O group has an overall negative charge.
These 2 groups therefore readily form weak bonds, called hydrogen bonds.
This causes what?
This causes the long polypeptide chain to be twisted into a 3-D shape
50
The secondary structure of proteins:
The linked amino acids that make up a polypeptide possess both -NH and -C = O groups on either side of every peptide bond.
The H of the -NH group has an overall positive charge, while the O of the -C = O group has an overall negative charge.
These 2 groups therefore readily form weak bonds, called hydrogen bonds.
This causes the long polypeptide chain to be twisted into a 3-D shape, such as what?
This causes the long polypeptide chain to be twisted into a 3-D shape, such as the coil known as an a-helix
51
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be what to give what?
The a-helices of the secondary protein structure can be:
1. Twisted
2. Folded even more
to give the 3-D structure of each protein
52
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the what 3-D structure of each protein?
The a-helices of the secondary protein structure can be twisted and folded even more to give the:
1. Complex
2. Often specific
3-D structure of each protein
53
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as what?
The a-helices of the secondary protein structure can be:
1. Twisted
2. Folded even more
to give the complex and often specific 3-D structure of each protein, known as the tertiary structure
54
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by what?
This tertiary structure is maintained by a number of different bonds
55
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on what?
Where the bonds occur depends on the primary structure of the protein
56
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include what?
These bonds include:
1. Disulfide bridges
2. Ionic bonds
3. Hydrogen bonds
57
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
Describe disulfide bridges
Disulfide bridges are:
1. Fairly strong
2. Therefore not easily broken
58
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
Ionic bonds are formed between where?
Ionic bonds are formed between any:
1. Carboyxl
2. Amino
groups that are not involved in forming peptide bonds
59
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
Ionic bonds are formed between any carboxyl and amino groups that are not involved in forming peptide bonds.
Ionic bonds are weaker than what?
Ionic bonds are weaker than disulfide bridges
60
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
Ionic bonds are formed between any carboxyl and amino groups that are not involved in forming peptide bonds.
Ionic bonds are weaker than disulfide bridges and are easily broken by what?
Ionic bonds are:
1. Weaker than disulfide bridges
2. Easily broken by changes in pH
61
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
Hydrogen bonds are what, but what?
Hydrogen bonds are:
1. Numerous
,but
2. Easily broken
62
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
It is the 3-D shape of a protein that is important when it comes to what?
It is the 3-D shape of a protein that is important when it comes to how it functions
63
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
It is the 3-D shape of a protein that is important when it comes to how it functions.
It makes each protein what?
The 3-D shape of a protein makes each protein distinctive
64
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
It is the 3-D shape of a protein that is important when it comes to how it functions.
It makes each protein distinctive and allows it to do what?
The 3-D shape of a protein makes each protein distinctive and allows it to:
1. Recognise
2. Be recognised by
,other molecules
65
The tertiary structure of proteins:
The a-helices of the secondary protein structure can be twisted and folded even more to give the complex and often specific 3-D structure of each protein, known as the tertiary structure.
This structure is maintained by a number of different bonds.
Where the bonds occur depends on the primary structure of the protein.
These bonds include disulfide bridges, ionic bonds and hydrogen bonds.
It is the 3-D shape of a protein that is important when it comes to how it functions.
It makes each protein distinctive and allows it to recognise, and be recognised by, other molecules.
The protein can then do what?
The protein can then interact with those other molecules in a very specific way
66
The primary structure of a protein
The primary structure of a protein is the sequence of amino acids found in its polypeptide chains
67
The primary structure of a protein is the sequence of amino acids found in its polypeptide chains.
This sequence determines its what?
This sequence of amino acids found in its polypeptide chains determines the protein's:
1. Properties
2. Shape
68
Following what, the primary structure of many other proteins is now known?
Following the elucidation of the amino acid sequence of the hormone insulin, the primary structure of many other proteins is now known
69
Following the elucidation of the amino acid sequence of the hormone insulin by who, the primary structure of many other proteins is now known?
Following the elucidation of the amino acid sequence of the hormone insulin by Frederick Sanger, the primary structure of many other proteins is now known
70
Following the elucidation of the amino acid sequence of the hormone insulin by Frederick Sanger when, the primary structure of many other proteins is now known?
Following the elucidation of the amino acid sequence of the hormone insulin by Frederick Sanger in 1954, the primary structure of many other proteins is now known
71
The secondary structure of a protein
The secondary structure of a protein is the shape the polypeptide chain forms as a result of hydrogen bonding
72
The secondary structure of a protein is the shape the polypeptide chain forms as a result of hydrogen bonding.
This is most often a what?
This is most often a spiral known as the a-helix
73
The secondary structure of a protein is the shape the polypeptide chain forms as a result of hydrogen bonding.
This is most often a spiral known as the a-helix, although what occur?
This is most often a spiral known as the a-helix, although other configurations occur
74
The tertiary structure of a protein is due to what?
The tertiary structure of a protein is due to the:
1. Bending
2. Twisting
of the polypeptide helix
75
The tertiary structure of a protein is due to the bending and twisting of the polypeptide helix into a what?
The tertiary structure of a protein is due to the:
1. Bending
2. Twisting
of the polypeptide helix into a compact structure
76
The tertiary structure of a protein is due to the bending and twisting of the polypeptide helix into a compact structure.
All 3 types of bond, disulphide, ionic and hydrogen, contribute to what?
All 3 types of bond:
1. Disulphide
2. Ionic
3. Hydrogen
,contribute to the maintenance of the tertiary structure
77
The quaternary structure of a protein arises from what?
The quaternary structure of a protein arises from the combination of:
1. A number of different polypeptide chains
2. Associated non-protein (prosthetic) groups
78
The quaternary structure of a protein arises from the combination of a number of different polypeptide chains and associated non-protein (prosthetic) groups into what?
The quaternary structure of a protein arises from the combination of a number of different polypeptide chains and associated non-protein (prosthetic) groups into a:
1. Large
2. Complex
protein molecule
79
The quaternary structure of a protein arises from the combination of a number of different polypeptide chains and associated non-protein (prosthetic) groups into a large, complex protein molecule, for example what?
The quaternary structure of a protein arises from the combination of:
1. A number of different polypeptide chains
2. Associated non-protein (prosthetic) groups
into a large and complex protein molecule, for example haemoglobin
80
Large proteins often form complex molecules containing a number of individual what chains that are what in various ways?
Large proteins often form complex molecules containing a number of individual polypeptide chains that are linked in various ways
81
Large proteins often form complex molecules containing a number of individual polypeptide chains that are linked in various ways.
There may also be non-protein (prosthetic) groups associated with the molecules, such as what?
There may also be non-protein (prosthetic) groups associated with the molecules, such as the iron-containing haem group in haemoglobin
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Large proteins often form complex molecules containing a number of individual polypeptide chains that are linked in various ways.
There may also be non-protein (prosthetic) groups associated with the molecules, such as the iron-containing haem group in haemoglobin.
Although the what is important to how a protein what?
Although the 3-D structure is important to how a protein functions
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Large proteins often form complex molecules containing a number of individual polypeptide chains that are linked in various ways.
There may also be non-protein (prosthetic) groups associated with the molecules, such as the iron-containing haem group in haemoglobin.
Although the 3-D structure is important to how a protein functions, it is the what that determines the what in the first place?
Although the 3-D structure is important to how a protein functions, it is the sequence of amino acids (the primary structure) that determines the 3-D shape in the first place
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The most reliable protein test is the what test?
The most reliable protein test is the Biuret test
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The most reliable protein test is the Biuret test, which detects what?
The most reliable protein test is the Biuret test, which detects peptide bonds
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The most reliable protein test is the Biuret test, which detects peptide bonds.
The Biuret test is performed as follows:
Place what in a test tube?
Place a sample of the solution to be tested in a test tube
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The most reliable protein test is the Biuret test, which detects peptide bonds.
The Biuret test is performed as follows:
Place a sample of the solution to be tested in a test tube and add what at what temperature?
Place a sample of the solution to be tested in a test tube and add an equal volume of sodium hydroxide solution at room temperature
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The most reliable protein test is the Biuret test, which detects peptide bonds.
The Biuret test is performed as follows:
Place a sample of the solution to be tested in a test tube and add an equal volume of sodium hydroxide solution at room temperature.
Add a few drops of what?
Add a few drops of very dilute (0.05%) copper (II) sulfate solution
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The most reliable protein test is the Biuret test, which detects peptide bonds.
The Biuret test is performed as follows:
Place a sample of the solution to be tested in a test tube and add an equal volume of sodium hydroxide solution at room temperature.
Add a few drops of very dilute (0.05%) copper (II) sulfate solution and do what gently?
Add a few drops of very dilute (0.05%) copper (II) sulfate solution and mix gently
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The most reliable protein test is the Biuret test, which detects peptide bonds.
The Biuret test is performed as follows:
Place a sample of the solution to be tested in a test tube and add an equal volume of sodium hydroxide solution at room temperature.
Add a few drops of very dilute (0.05%) copper (II) sulfate solution and mix gently.
What indicates the presence of peptide bonds and hence a protein?
A purple coloration indicates the presence of:
1. Peptide bonds
2. Hence a protein
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The most reliable protein test is the Biuret test, which detects peptide bonds.
The Biuret test is performed as follows:
Place a sample of the solution to be tested in a test tube and add an equal volume of sodium hydroxide solution at room temperature.
Add a few drops of very dilute (0.05%) copper (II) sulfate solution and mix gently.
A purple coloration indicates the presence of peptide bonds and hence a protein.
If no protein is present, the solution what?
If no protein is present, the solution remains blue
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Proteins perform many different roles in living organisms.
Their roles depend on their what shape?
Their roles depend on their molecular shape
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Proteins perform many different roles in living organisms.
Their roles depend on their molecular shape, which can be of what?
Their roles depend on their molecular shape, which can be of 2 basic types:
1. Fibrous proteins
2. Globular proteins
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Proteins perform many different roles in living organisms.
Their roles depend on their molecular shape, which can be of 2 basic types, fibrous proteins and globular proteins.
Fibrous proteins have what?
Fibrous proteins have structural functions
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Proteins perform many different roles in living organisms.
Their roles depend on their molecular shape, which can be of 2 basic types, fibrous proteins and globular proteins.
Globular proteins carry out what?
Globular proteins carry out metabolic functions
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Proteins perform many different roles in living organisms. Their roles depend on their molecular shape, which can be of 2 basic types, fibrous proteins and globular proteins.
Fibrous proteins have structural functions.
An example of a fibrous protein is what?
An example of a fibrous protein is collagen
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Proteins perform many different roles in living organisms. Their roles depend on their molecular shape, which can be of 2 basic types, fibrous proteins and globular proteins.
Globular proteins carry out metabolic functions.
Examples of globular proteins are what?
Examples of globular proteins are:
1. Enzymes
2. Haemoglobin
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Proteins perform many different roles in living organisms.
Their roles depend on their molecular shape, which can be of 2 basic types, fibrous proteins and globular proteins.
Fibrous proteins have structural functions.
Globular proteins carry out metabolic functions.
It is the very different what of each of these types of proteins that enables them to carry out their functions?
It is the very different:
1. Structure
2. Shape
of each of these types of proteins that enables them to carry out their functions
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Fibrous proteins form what?
Fibrous proteins form long chains
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Fibrous proteins form long chains that do what?
Fibrous proteins form long chains that run parallel to one another
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Fibrous proteins form long chains that run parallel to one another.
These long chains are linked by what?
These long chains are linked by cross-bridges
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Fibrous proteins form long chains that run parallel to one another.
These long chains are linked by cross-bridges and so form what?
These long chains:
1. Are linked by cross-bridges
2. So form very stable molecules
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Fibrous proteins form long chains that run parallel to one another.
These long chains are linked by cross-bridges and so form very stable molecules.
Collagen's molecular structure is that:
1. The primary structure is what?
Collagen's molecular structure is that the primary structure is an unbranched polypeptide chain
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Fibrous proteins form long chains that run parallel to one another.
These long chains are linked by cross-bridges and so form very stable molecules.
Collagen's molecular structure is that:
1. The primary structure is an unbranched polypeptide chain.
2. In the secondary structure, the polypeptide chain is what?
Collagen's molecular structure is that in the secondary structure, the polypeptide chain is very tightly wound
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Fibrous proteins form long chains that run parallel to one another.
These long chains are linked by cross-bridges and so form very stable molecules.
Collagen's molecular structure is that:
1. The primary structure is an unbranched polypeptide chain.
2. In the secondary structure, the polypeptide chain is very tightly wound.
3. Lots of what helps what?
Collagen's molecular structure is that lots of the amino acid glycine helps close packing
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Fibrous proteins form long chains that run parallel to one another.
These long chains are linked by cross-bridges and so form very stable molecules.
Collagen's molecular structure is that:
1. The primary structure is an unbranched polypeptide chain.
2. In the secondary structure, the polypeptide chain is very tightly wound.
3. Lots of the amino acid glycine helps close packing.
4. In the tertiary structure, the chain is what?
Collagen's molecular structure is that in the tertiary structure, the chain is twisted into a 2nd helix
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Fibrous proteins form long chains that run parallel to one another.
These long chains are linked by cross-bridges and so form very stable molecules.
Collagen's molecular structure is that:
1. The primary structure is an unbranched polypeptide chain.
2. In the secondary structure, the polypeptide chain is very tightly wound.
3. Lots of the amino acid glycine helps close packing.
4. In the tertiary structure, the chain is twisted into a 2nd helix.
5. Its quaternary structure is made up of what?
Collagen's molecular structure is that its quaternary structure is made up of 3 such polypeptide chains
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Fibrous proteins form long chains that run parallel to one another.
These long chains are linked by cross-bridges and so form very stable molecules.
Collagen's molecular structure is that:
1. The primary structure is an unbranched polypeptide chain.
2. In the secondary structure, the polypeptide chain is very tightly wound.
3. Lots of the amino acid glycine helps close packing.
4. In the tertiary structure, the chain is twisted into a 2nd helix.
5. Its quaternary structure is made up of 3 such polypeptide chains that are what?
Collagen's molecular structure is that its quaternary structure is made up of 3 such polypeptide chains that are wound together in the same way as individual fibres are wound together in a rope
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Where is collagen found?
Collagen is found in tendons
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Collagen is found in tendons.
What do tendons do?
Tendons join muscles to bones
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Collagen is found in tendons.
Tendons join muscles to bones.
When a muscle contracts, the bone is what?
When a muscle contracts, the bone is pulled in the direction of the contraction
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Collagen's molecular structure is that:
1. The primary structure is an unbranched polypeptide chain.
2. In the secondary structure, the polypeptide chain is very tightly wound.
3. Lots of the amino acid glycine helps close packing.
4. In the tertiary structure, the chain is twisted into a 2nd helix.
5. Its quaternary structure is made up of 3 such polypeptide chains that are wound together in the same way as individual fibres are wound together in a rope.
Collagen is found in tendons.
Tendons join muscles to bones.
When a muscle contracts, the bone is pulled in the direction of the contraction.
The individual collagen polypeptide chains in the fibres are held together by what?
The individual collagen polypeptide chains in the fibres are held together by bonds between amino acids of adjacent chains
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Collagen's molecular structure is that:
1. The primary structure is an unbranched polypeptide chain.
2. In the secondary structure, the polypeptide chain is very tightly wound.
3. Lots of the amino acid glycine helps close packing.
4. In the tertiary structure, the chain is twisted into a 2nd helix.
5. Its quaternary structure is made up of 3 such polypeptide chains that are wound together in the same way as individual fibres are wound together in a rope.
Collagen is found in tendons.
Tendons join muscles to bones.
When a muscle contracts, the bone is pulled in the direction of the contraction.
The individual collagen polypeptide chains in the fibres are held together by bonds between amino acids of adjacent chains.
The points where one collagen molecule ends and the next begins are what?
The points where one collagen molecule ends and the next begins are spread throughout the fibre
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Collagen's molecular structure is that:
1. The primary structure is an unbranched polypeptide chain.
2. In the secondary structure, the polypeptide chain is very tightly wound.
3. Lots of the amino acid glycine helps close packing.
4. In the tertiary structure, the chain is twisted into a 2nd helix.
5. Its quaternary structure is made up of 3 such polypeptide chains that are wound together in the same way as individual fibres are wound together in a rope.
Collagen is found in tendons.
Tendons join muscles to bones.
When a muscle contracts, the bone is pulled in the direction of the contraction.
The individual collagen polypeptide chains in the fibres are held together by bonds between amino acids of adjacent chains.
The points where one collagen molecule ends and the next begins are spread throughout the fibre, rather than what?
The points where one collagen molecule ends and the next begins are spread throughout the fibre, rather than being in the same position along it
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Think of the polypeptide chain as a piece of string. In a fibrous protein, what?
In a fibrous protein, many pieces of the string are twisted together into a rope
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Think of the polypeptide chain as a piece of string. In a fibrous protein, many pieces of the string are twisted together into a rope, while in a globular protein, what?
In a:
1. Fibrous protein, many pieces of the string are twisted together into a rope
,while
2. Globular protein, the pieces of string, usually fewer, are rolled into a ball
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You can simply refer to adding what to test for protein?
You can simply refer to adding Biuret reagent to test for protein
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The tertiary structure of a protein
The tertiary structure of a protein is the specific 3D shape formed due to attractions between the R group of the primary structure
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The quaternary structure of a protein
The quaternary structure of a protein is association of more than one polypeptide chain
