proteins Flashcards
what is an amino acid?
monomer of protein
what are the groups of an amino acid?
● amine
● R (variable)
● hydrogen
● carboxyl
what is a protein?
● polymer
● formed by long chains of amino acids joined together by peptide bonds
draw an amino acid
.
draw a simplified amino acid
.
draw a dipeptide
.
what is formed when 2 amino acids join together?
dipeptide + water
what reaction forms a dipeptide?
condensation
what bond is formed between 2 amino acids?
peptide bond (type of covalent bond)
where does the peptide bond form?
between carboxyl group of one amino acid and amine group of another amino acid
what is the primary structure of a protein?
● number and sequence of amino acids joined by peptide bonds
● proteins differ from each other as their primary structures are different
● determined by DNA sequence
what is the secondary structure of a protein?
● hydrogen bonds form between carboxyl and amine groups
● there are two shapes that can form within proteins due to the hydrogen bonds:
● α-helix
● β-pleated sheet
what is the tertiary structure of a protein?
● shape is help together by bonds between R groups
● hydrogen bonds - weak
● ionic bonds - weak, form between oppositely charged R groups
● disulphide bonds - only cysteine amino acids (as they contain sulfur)
what is the quaternary structure of a protein?
more than one polypeptide chain
what is an example of a protein with a quaternary structure?
haemoglobin
