Proteins Flashcards
What are amino acids made of?
Carbon, hydrogen, oxygen and nitrogen.
Examples of proteins:
Haemoglobin, enzymes, transport channels, hormones and in structures like keratin and collagen.
What is the molecular structure of an amino acid?
A carbon in the middle. Bonded upwards to an R group. Downwards to a hydrogen. To the left of an amino group and to the right a carboxyl group.
What changes in each amino acid!
The r group.
What does the amino group consist of?
An N bonded to two H’s.
What is a carboxyl group.
Carbon double bond O, single bond OH.
What are proteins made of?
Chains of amino acids.
How to join two amino acids?
Condensation reaction (taking out water)
What bond is formed when two amino acid chains join?
Peptide bond.
What is a dipeptide and polypeptide?
Dipeptide is two amino acid chains joined, polypeptide is more than two.
What is a secondary structure?
Folded amino chains held together by numerous weak hydrogen bonds
Examples of secondary structures?
Alpha helix and beta pleated sheet.
How is a tertiary structure formed?
Folding the secondary structures. Disulphide bridges, ionic bonds and hydrogen bonds.
What is the test for proteins?
Biuret A- sodium hydroxide
Biuret B- copper sulphate
Changes from light blue to lilac
Brief description of globular proteins?
Spherical in shape
Soluble in water
Weak hydrogen bonds
Eg- insulin, antibodies, haemoglobin
