Cell Cycle
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Cell Cycle The cell cycle begins when the cell is formed and ends when the cell divides and forms new cells.
description
Cell Cycle. The cell cycle begins when the cell is formed and ends when the cell divides and forms new cells. DNA. Before a cell divides, DNA is copied DNA is organized into structures called chromosomes DNA is in the nucleus. Cell Cycle ( Prokaryotic ) BACTERIA. - PowerPoint PPT Presentation
Transcript of Cell Cycle
Cell Cycle
The cell cycle begins when the cell is formed and ends when the cell divides and forms new cells.
DNA
Before a cell divides, DNA is copiedDNA is organized into structures called
chromosomesDNA is in the nucleus
Cell Cycle (Prokaryotic) BACTERIA
Bacteria are not complexBacteria contain ribosomes and a single
circular molecule of DNABacteria have no membrane bound
organelles, making cell division simpleCell division is called binary fission-
splitting into two partsThey make a copy of the DNA and split
with each cell containing a copy
Binary Fission in Bacteria
Bacteria
Binary Fission
Bacteria
Eukaryotic Cell DivisionCHROMOSOMESChromosomes contain lots of DNA and
proteinsNumber of chromosomes is different in
each organism-humans=46, potatoes=48, and fruit flies=8
Chromosomes can line up in pairs containing similar information (homologous chromosomes)
CHROMOSOMES
Making More Eukaryotic CellsINTERPHASE STAGE 1
Three stages, Interphase, Mitosis, and Cytokinesis
Stage 1(INTERPHASE)=Cell grows and copies organelles, centriole, and chromosomes
Strands of DNA and proteins are like loosely coiled thread
After chromosomes are duplicated, the copies are now called chromatids
Chromatids are held together by a centromere
INTERPHASE
INTERPHASE
Making More Eukaryotic Cells MITOSIS STAGE 2Three stages, Interphase, Mitosis, and
Cytokinesis
Stage 2 (Mitosis) Chromosome Separation
4 Phases OF MITOSIS = Prophase, Metaphase, Anaphase, and Telophase
Mitosis STAGE 2Separation – PHASE1Phase 1(Prophase) Mitosis beginsNuclear membranes break apartChromosomes condense into rod like
structuresTwo pair of centrioles move to opposite
sides of the cellFibers form between the centrioles and
attach to the centromeres
MITOSIS – STAGE 2PHASE 1 PROPHASE
MORE PROPHASE
Mitosis STAGE 2Separation – PHASE 2Phase 2 (Metaphase)Chromosomes line up along the equator of
the cellRemember M for Middle
METAPHASE
MORE METAPHASE
Mitosis – STAGE 2Separation – PHASE 3Phase 3 (Anaphase)Chromatids separate and are pulled to
opposite sides of the cell by fibers that are attached to the centrioles
Remember A for Apart
ANAPHASE
ANAPHASE
Mitosis – STAGE 2Separation – PHASE 4Phase 4 (Telophase)Nuclear membrane forms around two sets
of chromosomes and they unwindFibers disappearMitosis is completedRemember T for TwoThe kindergarten teacher said “Do not p
on the mat! (PMAT)
TELOPHASE
Stage 3 CYTOKINESIS-Animal Cell
After mitosis, the cytoplasm splits in two, (Cytokinesis)
Result is two identical cells, identical to the original cell they came from
After cytokinesis, cell cycle is complete and will start over again
Stage 3 CYTOKINESIS-Plant Cell
When plant cells divide, a cell plate forms and the cell is split in two
Cell plate becomes the new cell membrane that will separate the two cells
After split, new cell wall forms
CYTOKINESIS
CELL CYCLE COMPLETE!
