30 - Amino acids, proteins and DNA Flashcards
What is a zwitterion?
An amino acid with a negative charge and positive charge. (the H from the COOH goes to the NH2 to from COO- and NH3+
What happens to amino acids in an acid solution?
They are protonated. So COOH and NH3+
What happens to amino acids in alkaline solutions?
They are deprotonated. SO COO- and NH2.
What are amino acids joined by?
Peptide bonds
How can amino acids be separated and identified?
Thin-layer chromatography
What kind of specificity do enzymes show?
Stereospecificity
How can a drug act as an enzyme inhibitor?
By blocking the active site
How are carbons numbered in deoxyribose?
Clockwise
What carbon does an adjacent phosphate attach to on deoxyribose?
Carbon 3
How does cisplatin prevent DNA replication?
It bonds to two adjacent guanine Nitrogens.
Why does cisplatin cause side effects?
It prevents DNA replication in healthy cells. However it has a greater effect in fast-replicating cells, such as cancer cells and hair cells (chemotherapy causes hair loss)
Explain why urea is effective at separating complementary strands in DNA. (2)
Amino groups in urea
Are able to substitute for H bonds in double helix
Why are disulphide bridges the strongest?
They are covalent
