Presentation on theme: "THE CELL CYCLE 2.5 As eukaryotic cells grow and divide, they move through three distinct stages: interphase – cells grow and prepare to divide mitosis."— Presentation transcript:
1 THE CELL CYCLE2.5As eukaryotic cells grow and divide, they move through three distinct stages:interphase – cells grow and prepare to dividemitosis – cells start to dividecytokinesis – two cells are formed from oneInterphase:the cell carries out all normal life activitiesthe DNA is in very long, thin, and invisible strandsDNA is copied at end of interphase to get ready for divisionmost of the cell’s life is spent in interphaseHowStuffWorks Videos "Interphase: The Resting Stage"
2 2. Mitosis the DNA doubles, to get ready to be divided there are 4 phases of mitosisProphase:DNA thickens2 identical strands of DNA (copied during interphase) called chromosomeschromosome made of 2 identical sister chromatidseach chromatid held together by a centromerenuclear membrane disappearsYouTube - Mitosis: The Phases, Part 1 of 2, from Thinkwell Biology
4 ii) Metaphase iii) Anaphase centrioles move to either side of the cell chromosomes line up in the middle of the celliii) Anaphasecentromere splits and sister chromatids separatenow called ‘daughter’ chromosomesspindle fibres from centrioles pull them to opposite sides of the cell
5 iv) Telophase final stage of mitosis daughter chromosomes stretch out and get thinnernuclear membrane starts to form around each gp of daughter chromosomescell appears to have 2 nuclei (nucleus)
6 Cytokinesis cell’s cytoplasm divides cell membrane pinches off splits into 2 new daughter cellseach cell is identical to the original parent cellYouTube - Mitosis: The Phases, Part 2 of 2 from Thinkwell Biology