+ What are the main events of the cell cycle? Sections 8.4 thru 8.6
+ Chromosomes Chromosomes can be unduplicated (single) or duplicated (double) Duplicated chromosomes are composed of 2 identical sister chromatids that are held together by a centromere During cell division the sister chromatids of a duplicated (double) chromosome are pulled apart to form 2 unduplicated (single) chromosomes
+ Chromatin, chromosomes, chromatid… Chromatin – DNA when it is loose and threadlike Chromosome – DNA when it condensed; can be single or double Chromatid – half of a duplicated (double) chromosome
+ Cell Cycle
+ Interphase – the phase of the cell cycle in which the cell spends the majority of its time and performs its function; nuclear membrane is in tact; DNA in the form of chromatin; nucleolus is visible; made up of 3 stages G1 (first gap) – during this time the cell is growing and carrying out its function S (DNA synthesis) – during this time DNA is replicated G2 – (second gap) – during this time the cell continues to grow and prepares to for cell division
+ Cell Cycle M Phase (mitotic phase) – the phase of the cell cycle when the cell is dividing; made up of two stages Mitosis – division of the nucleus; has 4 phases: prophase, metaphase, anaphase, and telophase; some books have a 5 phase – prometaphase between prophase and metaphase Cytokinesis – division of the cytoplasm; begins during telophase of mitosis