The Cell Cycle & Mitosis BIOLOGY 12 The Cell Cycle & Mitosis

The Cell Cycle Animation of Cell Division

The Cell Cycle a series of events that cells go through as they grow and divide a cell grows prepares for division divides to form two daughter cells, each of which begins the cycle again

The Cell Cycle Interphase Mitosis Cytokinesis G1 phase S phase Prophase Metaphase Anaphase Telophase Cytokinesis

Interphase most of the cell’s time is spent in Interphase the period of growth between cell divisions during Interphase the cell will: increase in size synthesize new proteins and organelles undergo DNA replication

Interphase G1 Phase S Phase G2 Phase gap phase after mitosis, cell growth S Phase DNA replication (synthesis) G2 Phase gap phase, preparation for mitosis

Mitosis process where chromosomes are duplicated and distributed to daughter nuclei each daughter nucleus carries the same set of genetic information as the parent nucleus

Mitosis

Prophase first and longest phase the centrioles separate and take up position on either side of the nucleus spindles and spindle fibres begin to form

Prophase the chromatin condenses into chromosomes chromosomes join at the centromere the nuclear envelope breaks down

Prophase Spindle forming Centrioles Chromosomes (paired chromatids) Centromere

Metaphase the chromosomes line up at the metaphase plate (center of the cell) microtubles connect the centromere of each chromosome to the poles of the spindle

Metaphase Centromeres Centrioles

Anaphase chromosomes separate sister chromatids move towards opposite poles

Anaphase Chromatid (or individual chromosomes)

Telophase final stage of mitosis chromosomes gather at opposite ends of the cell and lose their distinct shape nuclear membrane begins to reform

Telophase Nuclear Membrane

Cytokinesis the final stage of the Cell Cycle, but begins during telophase division of the cytoplasm and organelles of a cell into two daughter cells

Cytokinesis in Animal Cells – the plasma membrane pinches together in Plant Cells – the cell plate grows outward from the middle each daughter cell is an exact replica of the mother cell

Cytokinesis

The Cell Cycle Animation of Interphase and Cell Division

Animal vs Plant Cells Animal Cells: Plant Cells: have centrioles cytoplasm pinches in during cytokinesis can divide anywhere, at any time Plant Cells: no centrioles cell plate forms from center division found in areas called meristems

Plant Cells

Questions What do you call the genetic information in each phase of the cell cycle? Why is it more accurate to call mitosis "nuclear replication" rather than "cellular division"? Draw a plant cell in one stage of Mitosis and label it. What role does the spindle play in the cell dividing? When and where does the cellulose wall (cell plate) form in the mother cell? How can you differentiate prophase from metaphase? What cellular events occur during interphase? Compare cytokinesis of animal cells with that of plant cells. Compare and contrast prophase and telophase.