Cell Division: Mitosis Licentious division - prostate cancer cells during division.

Interphase Three Stages 1.G 1 : First growth phase 2.S: DNA replication (S = synthesis) 3.G 2 : Second growth phase After Interphase, Mitosis starts (cell division)

CELL CYCLE VIDEO

Video of mitosis in process in actual cells DD3IQknCEdc

MITOSIS Mitosis is just one small part of the cell cycle. Definition: Mitosis is the process by which a eukaryotic cell separates into two identical daughter cells.eukaryotic

Chromosomes condense at the start of mitosis. DNA wraps around proteins (histones) that condense it. DNA double helix DNA and histones Chromatin Supercoiled DNA

DNA plus proteins is called chromatin. One half of a duplicated chromosome is a chromatid. Sister chromatids are held together at the centromere. Telomeres protect DNA and do not include genes. Condensed, duplicated chromosome chromatid telomere centromere telomere

Parent cell centrioles spindle fibers centrosome nucleus with DNA Interphase prepares the cell to divide. During interphase, the DNA is duplicated. Mitosis and cytokinesis produce two genetically identical daughter cells.

Mitosis divides the cell ’ s nucleus in four phases. During prophase, chromosomes condense and spindle fibers form.

Mitosis divides the cell ’ s nucleus in four phases. During metaphase, chromosomes line up in the middle of the cell.

Mitosis divides the cell ’ s nucleus in four phases. During anaphase, spindle fibers pull sister chromatids to opposite sides of the cell.

Mitosis divides the cell ’ s nucleus in four phases. During telophase, new nuclear membranes form and chromosomes begin to uncoil.

During Cytokinesis the cell divides into two daughter cells

STAGES OF MITOSIS INTERPHASE EARLY PROPHASE LATE PROPHASE METAPHASE ANAPHASE TELOPHASE CYTOKINESIS (daughter cells formed)

Why is it important for cells to make perfect copies of themselves? Their daughter cells need to be able to do the same thing they do. Muscle cells need to be muscle cells. Skin cells need to be skin cells, etc. If DNA is copied or separated incorrectly, cell won’t be able to function correctly.

How do chromosomes move during mitosis? By using spindle fibers! Let’s take a look at this in more detail…

The Spindle A spindle is a web type structure made up of microtubule fibers. It is essential for mitosis because it arranges the chromosomes into their correct positions in preparation for cell division. Mitotic center Microtubule A cell at metaphase a spindle

Mitosis in Action Blue shows DNA, green shows spindle fibers. interphase early anaphase metaphase late prophase early prophase prometaphase late telophase late anaphase

Comparing plant/animal cell mitosis. While you observe the next set of images, try to identify how these processes differ in plant and animal cells. Why do you think the images are so different? Cytokinesis is different in plant and animal cells In animal cells, the membrane pinches closed. In plant cells, a cell plate forms.

In animal cells, a cleavage furrow forms and separates daughter cells Cleave furrow in a dividing frog cell.

The plant cell wall forces cytokinesis to play by different rules

Microscopy Video of Mitosis in an Animal Cell Microscopy Video of Mitosis in a Plant Cell