BIOL 1030 Chapter Notes - Chapter 6: Sister Chromatids, Microtubule, Spindle Apparatus
Document Summary
23 pairs o/ chromosomes = gametes ( sex cells) eggs and sperm (designated as n)= haploid. Contains 2 major phases: interphase & mitotic phase. Interphase- cell growth & dna replication: mitotic- cell division. G1 phase: the cell is accumulating chromosomal dna and needed proteins: also accumulating energy for cell division. S phase: dna replication forms two copies of each chromosome ( sister chromatids: these chromatids are firmly attached at the centromere, the centromere is duplicated. The duplication will give rise to the mitotic spindle ( orchestrates chromosome movement: centrosome= a pair of rod-like centrioles at right angles. Centrioles organize cell division ( not common: g2 phase: the cell replenishes energy/ synthesizes proteins for chromosome manipulation, some organelles are duplicated cytoskeleton is dismantled, additional cell growth. Mitosis: prophase- chromosomes condense/ become visible. Centromeres move oppositely: prometaphase- chromosomes still condense. Spindle microtubules attach to kinetochores: metaphase- chromosome lineup in the middle. A spindle fiber attaches to each chromosomes: anaphase- centromeres split.
