Proteins Flashcards
(10 cards)
Which monomers and elements are proteins made of?
Proteins are made of amino acid monomers. Amino acids contain carbon, hydrogen, oxygen, and nitrogen atoms.
How do different amino acids differ?
The 20 different amino acids that are common in all living organisms differ only in their variable side chain (R group).
How are dipeptides formed?
Dipeptides are formed by the condensation of two amino acids, forming a peptide bond between them.
How are polypeptides formed?
Polypeptides are formed by the condensation of many amino acids, forming a peptide bond between them.
What is the primary structure of proteins?
The primary structure is the sequence of amino acids.
What is the secondary structure of proteins?
In the secondary structure of proteins, hydrogen bonds form between the amino acids in the chain. This causes the chain to fold into a beta-pleated sheet or coil into an alpha-helix.
What determines whether an alpha-helix or a beta-pleated sheet is formed?
Which of these is formed is determined by where hydrogen bonds are. This depends on the AA sequence and the R-group.
What is the tertiary structure of proteins?
The tertiary structure is the 3D folding of a polypeptide chain in a precise way, as determined by the amino acids of which it is composed. The tertiary structure is held together by hydrogen bonds, ionic bonds, and disulphide bridges.
What is the quaternary structure of proteins?
The quaternary structure is a number of polypeptide chains joined together (more than 1 polypeptide).
What is the process of the Biuret test for proteins?
1) Add a few drops of Biuret solution to the sample.
A positive result is a colour change to purple.
