Vocab:
- genome
- - genetic material of an organism
- chromosomes
- - thread like structures of DNA
- somatic cells
- - all body cells except the reproductive cells
- gametes
- - reproductive sperm and egg cells
- chromatin
- - contains a long DNA molecule and proteins that help support the chromosome
- sister chromatid
- - half of a chromosome
- centromere
- - region where two chromatids are closely attached
- mitosis
- - division of nucleus
- cytokinesis
- - division of cytoplasm
- meiosis
- - includes sex cells,yields non identical daughter cells that have only 1 set of chromosomes
- miotic (M) phase
- - mitosis & cytokinesis
- interphase
- - cell grows & copies chromosomes to prepare for cell division (includes G1,G2,S phases)
- G1 phase
- - growth
- G2 phase
- - growth continued
- S phase
- - cell copies chromosomes to prepare for cell division
- G0 phase
- - neutral non-dividing state
- prophase
- - microtoubles expand chromatin condenses
- prometaphase
- - nuclear envelope in pieces & microtoubles attach to the centrosome at kineticore proteins
- metaphase
- - (longest)chromosomes line up with the help from spindle fibers
- miotic spindle
- - microtuobles & proteins
- centrosome
- - microtouble organizing center
- aster
- - microtouble organizing center
- kinetochore
- - proteins on chromosomes that attach to microtoubles during prometaphase
- metaphase plate
- - imaginary plane equidistant from the spindle's two poles
- cleavage
- - actin microfilament ring that forms in animal cell cytokinesis
- cleavage furrow
- - grove on cell's surface
- cell plate
- - plant cell's way of dividing, a middle wall forms then gradually fuses with cell membrane
- binary fission
- - division in half
- origion of replication
- - place on chromosome where DNA replicates
- cell cycle control system
- - molecules that trigger & organize events in the cell cycle
- checkpoint
- - control point for stop & go signals
- cyclin
- - cyclic protein
- cyclin dependant kinases/Cdks
- - part of cyclin; leftover from previous MPF
- anaphase
- - (shortest) chromatids seperate & move to opposite poles
- telophase
- - 2 nuclei start forming chromosomes spread out as chromatin and the spindles & centrisomes dissapear
- MPF
- - M-phase promoting factor
answers to study guide questions:
1. The Prokaryotic genome has a single circular DNA loop and the Eukaryotic genome has several DNA bundles coiled togther in chromatin.
2. First, there's the G1 phase where the cell is growing,making organelles. Then there's the S phase where it stops growing and synthesizes DNA and __copies it. Then there's the G2 phase where the cell continues to grow organelles needed for division. Then the cell divides, then i gos into the __neutral G0 state.
3. Prophase: microtoubles expand chromatin condenses Prometaphase: nuclear envelope in pieces & microtoubles attach to the centrosome at __kineticore proteins Metaphase: (longest)chromosomes line up with the help from spindle fibers Anaphase: (shortest) chromatids seperate & move to __opposite poles Telophase: 2 nuclei start forming chromosomes spread out as chromatin and the spindles & centrisomes dissapear
4. The miotic spindle forms during prophase, in the cytoplasm, it's made of proteins and microtoubles. In animal cells, the spindle first forms with the __help of the microtouble-organizing center (centrosome). Centrosomes replicate and asters form at their ends, eventullay moving to opposite poles. __Each chromosome in the middle of the cell has a kinetochore that allows the kinetochore microtoubles to attach to it. The cell elongates becasue the __non-kinetochore microtoubles do not attach to any chromosomes.
5. Animal cell cytokinesis uses an actin microfilament ring that conracts and seperates (cleavage) while plant cells use vescicles from the Golgi that go __into the middle of the plant cell and forms a cell plate. Eventually the cell plate gets bigger and attaches to the cell membrane.
6. Binary Fission in Bacteria uses proteins to elongate the cell, similar to how eukaryotic cells use microtoubles. In prokaryotic Dinoflagellaites, __replicated chromosomes attach to the nuclear envelope and in Diatoms, a spindle develops within the nucleus, similar to a eukaryotic cell.
7. The master regulator gene p53 has damaged DNA and it doesn't stop cell division to repair the DNA
the checkpoints aren't regulated effectively due __to faulty DNA, the cell continually divides without stopping from the damaged control system. Normally, DNA would be repaired and cells too __unfixable would be destroyed by command of p53, but in cancer cells the p53 didn't stop the damaged cells from dividing.
8. Begign tumor cells stay in one spot and don't cause serious problems, malignant tumor cells spread to other organs altering their functions, and __metastatic tumor cells travel long distnaces and are often malignant.
9. Cyclins and CDKs help move the cells across phases. CDKs can activate or de-activate proteins based off the checkpoints. Cyclin and CDKs combine __to make M-phase promoting factor (MPF). Levels of cyclin rise in the G2 & S phases then fall during the M phase. The MPF phosphorylses a __protein, contributimg to the fragmentation of the nuclear envelope in prometaphase & contributes in condensing the chromosomes and forming the __miotic spindle in prophase. In anaphase, the MPF will enter into its' own cycle and its' noncyclin inactive CDK remains in the cell then it eventually __combines with cyclins.
