This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: - Somatic- All cells in the body except sex cells- Figure 13.3- Karyotype- Figure 12.10- Bacterial cells divide through binary fission- Eukaryotes have linear chromosomes- Genome- cells total DNA- Chromosomes come in pairs, chromosomes with same info are homologous- The X looking chromosomes only show up when cells are replicating, they are called sister chromatids, centromere holds them together.- Mitosis occurs when you have a cell that divides into 2, the cells are identical- Do this for Growth and Regeneration- Karyokinesis- division of the nucleus- Cytokinesis- division of the cytoplasm- Mitosis is broken up into different phases, but once the cycle begins there is no pausing between stages.- Interphase from one end of cell division to beginning of next- Mitotic phase when cells divide- Figure 12.5- Interphase is not a part of mitosis o Must occur for mitosis to occur o Doesnt appear to be doing anything. o The DNA is organized into chromatin o Nuclear envelope and Nucleolus are present o Animal cells have centrioles, plant cells dont. o Centrioles are located in the centrosomes region. This is where microtubules are made. o DNA replicates- When 2 chromosomes are together (X) they are celled sister chromosomes ( called a dyad) o Centromere is the region that has the kinetochore- Prophase- 1 st phase of mitosis o Chromatin condense into chromosomes o Nuclear envelope and Nucleolus disappear. o Centrioles migrate to opposite ends, as they travel they place microtubules, used for spindle. Some of spindles attach to chromosomes kinetochore, these move the chromosomes. Ones that dont attach to chromosomes, called non-kinetochore microtubules, these elongate the cell.- Asters- the radial arrays of shorter microtubules that extend from the centrosomes- Figure 12.6- kinetochore specialized protein structure located at the centromere- Metaphase- longest phase of mitosis, lasting about 20 minutes o Chromosomes align at equator of cell, this is the metaphase plate . o Microtubules can be made and disassembled- Anaphase o Shortest stage of mitosis, lasting only a few minutes o Separate sister chromatids o Non-kinetochore microtubules elongate the cell- Telophase o Cleavage Furrow develops o Nuclear Envelope develops- Cytokinesis involves the formation of a cleavage furrow (animal cells) or a cell plate (plant cells)- Dynein is the motor molecule for mitosis- Specialized cells exit the cell cycle, which is Interphase to mitosis, back to Interphase o Liver cells do divide to when they need to.- Figure 12.11- Binary fission (prokaryotes) circular chromosomes; origin of replication- Figure 12.14- Cell cycle control system has 3 checkpoints: G1, G2, M- If a cell is permanently stopped at G1, then its called G0....
View Full Document
- Fall '07