Amino Acids Lecture Flashcards
Another name for R-groups
Side chains
Another way of writing primary/secondary/tertiary?
1y/2y/3y
How many natural amino acids are there?
20
Define primary structure
Linear sequence of amino acids joined by peptide bonds
What are nucleic acids built from?
Nucleotides
Give two important functions of nucleic acids
Determine structure of DNA
Basis of energy transfer molecules e.g. ATP
Name three components of a nucleotide
A pentose (5C) sugar
A nitrogenous base
A phosphate group
What are the two types of nitrogenous base found in nucleotides?
Purines or pyrimidines
What pentose sugar is found in RNA?
Beta-ribose
What pentose sugar is found in DNA
Beta-2-deoxy-ribose
What are the two types of purines found in nucleic acids?
Adenine and guanine
What pyrimidines are found in nucleotides?
Cytosine, thymine, uracil
What are proteins?
Biomolecules that contain many amine bonds, formed by joining amino acids together
How are D amino acids recognised?
NH3+ group in right side of Fischer projections
How are L amino acids recognised?
NH3+ group on left side of Fischer projections
In what form are most naturally occurring amino acids?
L form
What bonds form between two cysteine residues?
Disulphides bridges, giving tertiary structure more strength
Name the three groups of amino acid based on their R-group
Hydrophobic, hydrophobic aromatic, hydrophilic
What bonding is present in primary structure of proteins?
Peptide bonds
What is the secondary structure?
Regular folding of regions of polypeptide chain
What bonding is present in the secondary structure
Hydrogen bonds
Name the two possible arrangements of the secondary structure
Alpha helix and beta sheet
Describe the arrangement of the alpha helix
All R-groups point outwards
What is a nucleoside?
A dimer formed when a pentose sugar is linked to a nitrogenous base
Where does the link form when a purines base links to a pentose to form a nucleoside
C1 of pentose and N9 of purine base
Where does the link form in a pyrimidine nucleoside?
C1 of pentose and N1 of pyrimidine
How is the tertiary structure held together
Van der waals, hydrogen bonds, ionic bonds, disulphide bridges
How is quaternary structure formed?
Interactions of different polypeptide chains
Give an example of a structural protein
Collagen, found in connective tissue, related disease is scurvy
Give an example of a hormone
Insulin, regulates blood glucose levels, related disease is diabetes
Give an example of a protein involved with immunity
Immunoglobins (antibodies)
Give an example of a transport protein
Haemoglobin, transports oxygen around body
Give an example of an enzyme
Hexokinase, carries out first step of glycolysis
Give an example of a contractile protein?
Actin and myosin
Give an example of a storage protein
Ferritin, stores iron in the liver
What is transcription?
Synthesis of RNA from DNA
What is translation?
Synthesis of proteins from RNA
Structural name of adenine
6-aminopurine
Structural name of guanine
2-amino-6-hydroxypurine
