MEDRADSC 3U03 Lecture Notes - Lecture 2: Chromosome Abnormality, Centromere, Ionizing Radiation

• School: McMaster University
• Department: Medical Radiation Sciences
• Course: MEDRADSC 3U03
• Professor: Cathy Hayward

Document Summary

Tissues appear to be more radiosensitive" if their cells are less well differentiated, have a greater proliferative capacity and divide more rapidly . Rapid tissue: epithelial origins more cancers occur. When the cell is injured, they will try to repair. If cell takes a longer time to divide, have more time to repair. Understanding how celsl grow and die is of central importance to understand tumors. The cell cycle is defined as the average interval between successive divisions/mitoses. All proliferating mammalian cells have a cell cycle: m followed by g1, s and g2. Relative lengths of each phase vary depending on cell type: major contribution is due to differences in g1. If cells stop cycling they are said to be in g0. Radiation effects on cell cycle cells have several strategies to deal with radiation-induced. Unstable or lethal aberrations result from asymmetric exchange of genetic material. Strong correlation between cell killing and # of aberrations.