Lec 3 Deoxyribonucleic Acid and Chromosomal Damage and Damage Response Flashcards
1
Q
Deoxyribonucleic Acid and Chromosomal Damage and Damage Response (4)
A
- Base damage
- Single-strand breaks
- Double-strand breaks
- DNA-DNA & DNA-Protein cross links
2
Q
Most important damage type.
A
Double strand breaks
3
Q
Repaired by nonhomologous end-joining or homologous recombination
A
Double strand breaks
4
Q
Accounts for many of the ionizing radiation-induced mutations
A
Nonhomologous end-joining
5
Q
A single photon may cause multiple ionizations in DNA.
A
Clustered DNA damage
6
Q
Difficult to repair and is believed to be responsible for most radiation cell killing, carcinogenesis, and heritable effects.
A
Clustered DNA damage
7
Q
Double-strand breaks
- Prior to chromosomal duplication
- After chromosomal duplication
- Cells are most radiosensitive
- Cells are less radiosensitive (latter part)
- cells are least radiosensitive.
A
- Chromosome aberration (double arm)
- Chromatid aberration (single arm)
- G2 and mitosis phase
- G1 phase
- S phase
8
Q
5 types of abberation
A
- Ring chromosome
- Dicentric chromosome
- Anaphase bridge
- Translocations
- Small deletions
