Mitosis Check
1. Define mitosis and tell why it is important.
~Division of one cell into two cells which are identical to the original.
~Growth, Repair, Maintenance (Reproduction of Euk Single-Celled Organisms)
2. Differentiate between mitosis and cytokinesis.
Mitosis is division of nucleus. Cytokinesis is division of the cytoplasm.
3. Why do chromosomes form chromatin?
So that the DNA is to unzip
4. What is the purpose of the S phase of the cell cycle?
Replicate DNA
5. In what phase of the cell cycle does replication occur? Why is it important?
S phase—so each new cell has a full set of DNA
6. How is binary fission different from mitosis?
No nucleus, no spindle, no line-up of chromosomes in binary fission
7. What is a plasmid? Why is it important?
~Tiny loop of DNA
~Allows for recombination (variation) in bacteria
8. What is the role of a spindle fiber? A centriole?
~Sort the microtubules
~Arrange the microtubules? Not sure….
9. What is a meristmatic region? Where can you fine one?
~Special growth region in plants where lots of cell division occurs
~Occurs in the ends of roots and stems
10. Compare and contrast DNA in a prokaryotic and a eukaryotic cell.
Both—double helix, A-T, C-G, Coil to fit in cell
Prokaryotic—loop attached to the cell membrane
Eukaryotic—Strands in nucleus
True/False
1.
2.
3.
4.
5.
6.
Asters form from centrioles. F
Plants form cleavage furrows. F
Centrioles can replicate. T
Chromosomes are joined by chromatin. F
Centromeres attach to centrioles. F
The nuclear membrane reforms in anaphase. F
7. Chromatids form as a result of replication. T
8. Centromeres break apart in telophase. F
9. DNA strands in eukaryotic cells exist in multiples of two. T
10. The “poles” are created by the spindle fibers. T/F
11. Two pairs of chromatids attach to each spindle fibers. F
12. DNA is not visible in interphase T
13. The G2 phase helps a cell get ready for mitosis. T
14. Cells stuck at G0 do not divide. T
15. Bacteria are all clones of each other (no recombination). F (mutations)
16. If a skin cell does mitosis it produces clones of itself. T
17. The major purpose of metaphase is to separate chromatids. F
18. Humans have 92 strands of DNA in metaphase T