Cell Cycle/Cell Division Mitosis and cytokinesis
DNA vs RNA DNA Sugar= deoxyribose Nitrogen bases a. Adenine b. Guanine c. Cytosine d. Thymine Double stranded molecule RNA Sugar= ribose Nitrogen bases a. Adenine b. Guanine c. Cytosine d. Uracil Single stranded
Basic information about chromosomes A. Homologous or paired chromosomes B. Chromatids and centromeres C. Alleles 1- homozygous alleles 2- heterozygous allele
Steps to Mitosis Interphase Steps to Mitosis Prophase Metaphase Anaphase Telophase Cytokinesis
Interphase 1- DNA replication 2- transcription and translation (normal cell growth)
Prophase Chromatin Condense Proteins condense on centromeres Nuclear envelope dissolves (DNA free in cell) Animals Centrioles form spindle fibers
Metaphase Metaphase Plate (chromosomes line up in the middle of the cell) Highly organized so that both cells get exactly the same DNA Spindle fibers completely attached to centromeres
Anaphase Paired chromosomes are pulled to opposite sides Each end is considered a polar end
Telophase Chromatids end up at separate poles, spindle fibers begin to dissolve New nuclear envelope begins to form Cell starts to pinch off through cytokinesis (close to form two new daughter cells)
Cytokinesis Division of all the rest of cell parts (organelles) Animals actin around the center of cell contracts pinching off two cells Plants new cell plate created between the two cells
Mitosis Animation http://www.biology.arizona.edu/cell_bio/tutorials/cell_cycle/cells3.html
Significance of Mitosis A. Growth B. Maintenance (repair and replacement)--> intestinal lining/RBC’s) C. Asexual reproduction
Vocabulary cytokinesis: centromere chromosome diploid: haploid: interphase: metaphase: mitosis: prophase: telophase:
Study Questions 1. What are the specific functions of mitosis? 2. List and discuss the two major processes associated with interphase.
3. Describe how cytokinesis differs in plant and animal cells. 4. Make a chart listing the major activities and events associated with each of the mitotic phases.