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protein a level biolgy AqA

i need help with this two questions. how does the sequence of amino acid affect the function of a protein(6marks). how does the number of amino acid effect the structure of a protein or funcation of a protein ( 6 marks)
Original post by nnn121337
i need help with this two questions. how does the sequence of amino acid affect the function of a protein(6marks). how does the number of amino acid effect the structure of a protein or funcation of a protein ( 6 marks)

Remember the protein structure
Primary structure - amino acids sequence joined by peptide bond
Secondary structure - hydrogen bonds between non-R groups to form alpha helix or beta plated sheet
Tertiary structure - 3D shape formed by hydrogen bonds, hydrophobic/hydrophilic region, sulphide bond and ionic bond
Quaternary structure - hydrogen bonds, hydrophobic/hydrophilic region, sulphide bond and ionic bonds between polypeptide chains (tertiary structures)

The 2 questions are applying the above knowledge.
Reply 2
Original post by BankaiGintoki
Remember the protein structure
Primary structure - amino acids sequence joined by peptide bond
Secondary structure - hydrogen bonds between non-R groups to form alpha helix or beta plated sheet
Tertiary structure - 3D shape formed by hydrogen bonds, hydrophobic/hydrophilic region, sulphide bond and ionic bond
Quaternary structure - hydrogen bonds, hydrophobic/hydrophilic region, sulphide bond and ionic bonds between polypeptide chains (tertiary structures)

The 2 questions are applying the above knowledge.

i know that but i don't know how to apply it can you help me please.
Reply 3
Original post by nnn121337
i know that but i don't know how to apply it can you help me please.

Can someone please help i got a mock exam.
Original post by nnn121337
i know that but i don't know how to apply it can you help me please.

You need to understand it, not just memorise it.
The sequence of amino acids is the primary structure - influences the secondary structure and tertiary structure (due to interactions between R groups). Link it to your knowledge. High amount of hydrophilic R groups - a globular protein, soluble in water, such as insulin. High amount of hydrophobic R groups - fibrous proteins, keratin, elastin… flexible, insoluble.
Reply 5
Original post by BankaiGintoki
You need to understand it, not just memorise it.
The sequence of amino acids is the primary structure - influences the secondary structure and tertiary structure (due to interactions between R groups). Link it to your knowledge. High amount of hydrophilic R groups - a globular protein, soluble in water, such as insulin. High amount of hydrophobic R groups - fibrous proteins, keratin, elastin… flexible, insoluble.

is this right. a change in the sequence of amino acid means a change in the primary structure of protein the primary structure of a protein helps to determine the shape of a protein therefore its function. A change in the sequence of amino acid could mean that a change in the hydrogen bond which causes the polypeptide chain to fold and twist into the wrong shape alpha helix or beta pleated sheet. A change in the shape effect the tertiary structure the wrong shape can be twisted and folded even more to form more bonds between different parts of the polypeptide bond hydrogen bond form in the wrong place, disulphide bridge and ionic bonds. this all means the 3d structure is changed a change in the shape means that protein is not able to carry out its funcation. the Quaternary structure is also effected as different polypeptide chains are found assemble in the wrong way.

I don't know how to do the second question. i am sorry for bothering you too much.
Yes, you could add in examples such as enzyme active sites or protein channels etc to show how the specific sequence of amino acids would give an exact shape which is essential to its function. and you can discuss how the repeating pattern in a fibrous protein is important in creating the strong structural proterties. eg keratin
(edited 1 year ago)
Reply 7
Original post by totallyfine
Yes, you could add in examples such as enzyme active sites or protein channels etc to show how the specific sequence of amino acids would give an exact shape which is essential to its function. and you can discuss how the repeating pattern in a fibrous protein is important in creating the strong structural proterties. eg keratin

i don't know how to answer this question though how does the number of amino acid effect the structure of a protein or funcation of a protein ( 6 marks)
Yeah, that's not a common question I have seen before.
I think they are largely the same question. However, larger proteins do form different 'domains' in their structure which provide different roles. For example, regions containing alphs helix structures are found in protein channels and receptors.

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