Amino Acids Flashcards
1
Q
What groups do amino acids contain?
A
- COOH (carboxyl group)
- NH2 (amine group)
2
Q
What does amphoteric mean?
A
- Can act as an acid or a base because of basic and acidic groups
3
Q
How do acid / base reactions occur in amino acids?
A
- Amine group reacts with acids
- Carboxyl group reacts with bases
4
Q
How does an amino acid form a zwitterion? What properties does it bring?
A
- Intramolecular reaction
- NH3+ group forms
- COO- group forms
They are can be strong intermolecular forces of attraction between amino acids, so can be soluble crystalline solids.
5
Q
How are zwitterions useful?
A
Can be used as buffer solutions resisting changes in small pH changes.
6
Q
How do amino acids act as buffer solutions?
A
- Zwitterions
- COO- accepts H+ (lowering pH if acid is added)
- NH3+ donates H+ (raising pH if base is added)
7
Q
What is the isoelectric point?
A
Where neither positively or negatively charged ion dominate and amino acid exists as neutral zwitterion.
