Cell Cycle Interphase, Mitosis, Cytokinesis, and Cancer
Cell Division One cell divides into 2 new identical daughter cells. Chromosomes carry the genetic information (traits) of the cell
How many Chromosomes are in each of your cells? 46 individual ones - (23 pairs) Single Chromosome Diploid Cells Having two of each chromosome Haploid Cells Having only one chromosome of each “pair”
Normal Karyotype
Abnormal Karyotype
Gene Expression Cell differentiation occurs because cells have the ability to turn off most genes and only work with the genes necessary for the cell to do its specific job.
Cell Cycle Made of three parts – Interphase – Mitosis – Cytokinesis
Interphase The time in between cell divisions when cells grow; longest part of the cell cycle.
Interphase -broken into 3 different parts: 1. G 1 - First Growth The cell grows in size and increases # of organelles 2. S - Synthesis DNA replicates during this time Happens rapidly 3. G 2 - Second Growth Increase the size of the cell again and increase the # of organelles again
Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming
Mitosis Prophase – Longest phase of mitosis – Early prophase: Chromatin coils up into visible chromosomes Sister chromatids are exact copies of each other
Mitosis Prophase – Late Prophase: The nucleus begins to disappear Centrioles move to opposite ends of the cell Spindle fibers form between the centrioles
Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming
Prophase (centrioles)
Spindle
Mitosis Metaphase – Chromosomes attach to the spindle fibers by their centromeres. – Chromosomes line up in the middle of the cell.
Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming
Mitosis Anaphase – Centromeres split – Chromatid pairs separate and pull apart to opposite sides of the cell
Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming
Mitosis Telophase – Chromosomes uncoil – Nuclear membrane reappears – A new membrane starts to form between the two new nuclei
Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming
Cytokinesis Cytoplasm divides In Animals: cell membrane pinches in to form a furrow In Plants: a cell plate is created to form a new cell wall
Centrioles Chromatin Interphase Nuclear envelope Cytokinesis Nuclear envelope reforming Telophase Anaphase Individual chromosomes Metaphase Centriole Spindle Centriole Chromosomes (paired chromatids) Prophase Centromere Spindle forming
Cytokinesis
Control of the Cell Cycle If uncontrolled cell division occurs, serious health issues are possible for the surrounding tissue and the entire organism; this malfunction causes cancer. – Interfer with normal processes – Spread to other tissue (metastasize) – Crowd out healthy tissue
Control of the Cell Cycle – This can be cause by many factors: Environmental Smoking Pollution Radiation Viral Infections