Biology: Proteins Flashcards
How many amino acids are common in all organisms?
The 20 amino acids that are common in all organisms differ only in their side group.
Who is a peptide bond formed?
A Condensation reaction between two Amino acids forms a peptide bond
How are Dipeptides and Polypeptides?
- Dipeptides are formed by the Condensation of two Amino acids.
- Polypeptides are formed by the Condensation of many amino acids.
What Bonds hold the structure of proteins?
- Ionic bonds
- Hydrogen bonds
- Disulfide bridges
What is the primary structure of Proteins?
Sequence of amino acids in the polypeptide chains held together by peptide bonds
What are secondary structure of Proteins?
Folding or cooling of the polypeptide chain into an alpha helix or a beta pleated sheet held by hydrogen bonds.
What are Tertiary structure of Proteins?
The further folding of the secondary structure to form a 3D shape. Held by Ionic bonds, Disulfide Bridges and Hydrogen Bonds
What are quaternary structure of Proteins?
The 3D shape that forms when there is more than one polypeptide chain e.g. hemoglobin
Hydrogen bonds hold the polypeptide chain in its secondary structure. which parts of the Amino acids do the hydrogen bonds form between?
Hydrogen of an amine group and oxygen of a carboxyl group.
What is the strongest to weakest bonds that hold tertiary structure?
- Disulfide Bridge
- Ionic Bonds
- Hydrogen Bonds
What is the name of the bond that links the amino acids together?
Peptide Bond
Which chemical groups will you find at each end of the polypeptide?
Amine group
Carboxyl Group
What are Globular Proteins?
- Globular Proteins are folded into a spherical like tertiary or quaternary structure
- Proteins are large molecules but when folded, as they are in Globular Proteins, they have solubility. The parts of the polypeptide chain with hydrophobic R groups in the centre of the molecule and the hydrophilic R groups are on the outside.
Can R groups change?
Yes, the R group can change. Different R groups give different types of amino acids. There are twenty different, naturally occuring amino acids.
What determines the position of the bonds in Protein structure?
The sequence of amino acids.
