Becker's World of the Cell (9th Edition)
9th Edition
ISBN: 9780321934925
Author: Jeff Hardin, Gregory Paul Bertoni
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 24, Problem 24.3PS
Chromosome Movement in Mitosis. It is possible to mark the microtubules of a spindle by photobleaching with a laser microbeam (Figure 24-29). When this is done, chromosomes move toward the bleached area during anaphase. Are the following statements consistent or inconsistent with this experimental result? In each case, explain your answer.
- (a) Microtubules move chromosomes solely by disassembling at the spindle poles.
- (b) Chromosomes move by disassembling microtubules at their kinetochore ends.
- (c) Chromosomes are moved along microtubules by a kinetochore motor protein that moves along the surface of the microtubule and “pulls” the chromosome with it.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Question.
The function of
FG-nucleoporins within the nuclear pore complex is to:
shield large, hydrophilic, unchaperoned proteins from entering the nucleus.
prevent small, hydrophobic proteins from entering the nucleus.
cleave the nuclear localization sequence (NLS) from the protein to be imported.
aid GAP in the hydrolysis of GTP to GDP.
All of the above.
Question 5,
Ultimately, the entire process of nuclear protein import is driven by:
the concentration gradient of the imported protein across the nuclear
membrane.
the localization of Ran
FG-nucleoporins in the nuclear pore complex (NPC)
GTP hydrolysis
None of the above
Question 6
During the process of nuclear import, a GEF works in the:
cytoplasm to exchange GTP for the GDP bound to Ran
cytoplasm to use GTP to release Ran from importin
nucleus to exchange GTP for the GDP bound to Ran
nucleus to activate the intrinsic GTPase activity of Ran
In Neurospora, a cross was made: ab x ++; and 100 asci were scored and placed into the
seven possible classes as shown below:
Class: 1 2 3 4 5 6 7
ab a+ ab ab ab a+a+
ab a+ a++b+++b+b
+++b+++++++b++
+++b +b a+ ab a+ ab
69 0 10 17 112
a. Determine whether these genes are on the same chromosome or different
chromosomes. Why?
b. If linked on the same chromosome are they on the same or opposite arms. Why?
c. Determine the map distance between genes (if linked), and between the genes and their
Dynamic instability causes microtubules either to grow or to shrink rapidly. Consider an individual microtubule that is in its shrinking phase.
What would need to happen at the end of the microtubule in order for it to stop shrinking and to start growing again? Be specific!
What would happen if only GDP, but no GTP, were present in the solution?
What would happen if the solution contained an analog of GTP that cannot be hydrolyzed?
Chapter 24 Solutions
Becker's World of the Cell (9th Edition)
Ch. 24 - Prob. 1QCh. 24 - Which DNA sequences are more alike: a pair of...Ch. 24 - Suppose you treat rapidly dividing tissue culture...Ch. 24 - Cyclin D is part of the G1 Cdk-cyclin complex....Ch. 24 - Both EGF (a mitogen) and TGF (when acting as an...Ch. 24 - A knockout mouse has been produced using the...Ch. 24 - Cell Cycle Phases. Indicate whether each of the...Ch. 24 - QUANTITATIVE The Mitotic Index and the Cell Cycle....Ch. 24 - Chromosome Movement in Mitosis. It is possible to...Ch. 24 - Cytokinesis. Predict what will happen in each of...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- Also explain why this enzyme does not break down proteins on its way to the lysosome but becomes actively only when (and just before) it has entered the lysosome.arrow_forwardDisdis -how do RB and p53 negatively regulate the cell cycle in G1? describe the events that occur in the initiation and elongation of DNA replication in S phase.arrow_forwardWound healing and mitotic rates in the damaged cornea of a mouse. The level of DNA replication in corneal epithelial cells in mice is high in the morning and low in the afternoon/evening. As a consequence, injury in the morning is expected to lead to accelerated entry into mitosis and wound repair compared to injury in the afternoon/evening. Shaded areas indicate dark periods and ZT stands for Zeitgeber Time (24 hour period).arrow_forward
- Which statements are true? Explain why or why not.1 Because the DNA double helix is only 2 nm wide—well below the limit of resolution of the light microscope—it is impossible to see chromosomes in living cells withoutspecial stains.2 A fluorescent molecule, having absorbed a singlephoton of light at one wavelength, always emits it at a longer wavelength.arrow_forwardTime (h) 0 1 3 6 12 Mouse thymus cells were treated with 10 micromolar dexamethasone to induce apoptosis. At the indicated times the chromosomal DNA was extracted and analyzed by gel electrophoresis, which separates the DNA fragments based upon size differences. When cells undergo apoptosis their DNA is cut into fragments that are approximately multiples of 200 base pairs. This results in a characteristic “ladder" appearance when the fragments are separated by gel electrophoresis, as shown above. Based upon what you know about eukaryotic chromatin, explain why this pattern of DNA fragments is obtained. 6.arrow_forwardGenetic application problem A couple in which the woman belongs to group 0 Rh- and the man is AB Rh + claim as theirs a baby whose blood is A Rh +. What would you think as a judge about this lawsuit? Explain...arrow_forward
- True or False. Topoisomerase I does not require ATP to break and rejoin DNA strands because the energy of the phospho-diester bond is stored transiently in a phospho-tyrosine linkage in the enzyme’s active site. Explain your answer in 2-3 sentences.arrow_forwardtraffic deaths in 10 years. Does daylight savings time increase the number of traffic deaths? (Many countries are in the process of getting rid of the time change - even though the Senate did vote to stop the time change the legislation seems to have stalled (as usual!)). 6) Epistasis is a phenomenon in which one gene controls the expression of another. In one case, a dihybrid cross should yield a 9:3:4 ratio. You collect the following data on mice: black coat: 218 Is there any reason to doubt the ratio of 9 black: 3 brown : 4 white? brown coat: 76 white coat: 89arrow_forwardTrue or False. De-acetylation of histone tails allows nucleosomes to pack together into tighter arrays, which usually reduces gene expression. Explain your answer in 1-2 sentences.arrow_forward
- 5) Using FRAP (Fluorescence Recovery After Photobleaching), you can measure the diffusion rate of membrane proteins. You attach a fluorescent marker to your protein of interest, bleach a small region of the cell membrane with an intense laser light, and determine the time it takes for the bleached spot to recover fluorescent signal (see figure below). (a) (b) Bleach Laser bleaching of fluorescent marker Fluorescence intensity recovery Recovery Time How would the recovery time of your protein change if the membrane contained a higher concentration of unsaturated fatty acids? Why? How would the recovery time of your protein change if you conducted the experiment at a lower temperature? Why? How would the recovery time of your protein change if it were anchored to the membrane skeleton? Why?arrow_forwardDynamic instability causes microtubules either to grow or to shrink rapidly. Consider an individual microtubule that is in its shrinking phase. What would happen if only GDP, but no GTP, were present in the solution.arrow_forwardPaclitaxel stabilizes microtubules by inhibiting the disassembly of the tubulin subunits. What phase of (mitosis) should the cell cycle be arrested in by addition of paclitaxel to dividing cells? Explainarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
BiochemistryBiochemistryISBN:9781305577206Author:Reginald H. Garrett, Charles M. GrishamPublisher:Cengage Learning
Biochemistry
Biochemistry
ISBN:9781305577206
Author:Reginald H. Garrett, Charles M. Grisham
Publisher:Cengage Learning
cell division of meiosis and mitosis; Author: Stated Clearly;https://www.youtube.com/watch?v=A-mFPZLLbHI;License: Standard youtube license