To determine:
The type of cell division that is represented in the figure and the relationship between the parts of figure.
Introduction:
Meiosis, also known as the reductional division, is the second type of cell division that takes place in eukaryotes. The cell division is marked by a decrease in the chromosome number to half. This type of cell division allows the recombination of the genes on the chromosome to produce a zygote. The two diploid cells undergo division to produce four haploid daughter cells.
To determine:
The difference between cohesion of centromeres and cohesion of arms.
Introduction:
The chromosomes are condensed structures that are formed during the early phases of cell division from the loose network of chromatin thread and then regain their original structure after being divided into daughter cells.
To determine:
The mechanism that keeps the chromosomes together during metaphase.
Introduction:
The human consists of 23 pairs of chromosomes, condensed form of chromatids which divide during cell division into daughter cells. The human has 22 autosomes and one pair of sex chromosomes. The sex chromosomes determine the sex in an individual based on the type of sex chromosomes that are present in the fusing gametes.
To determine:
The role of shugoshin and the enzyme it inhibits.
Introduction:
The chromosome from chromatids are formed through the process of supercoiling. The chromatin fibres are condensed into thick structures called the chromosomes. This chromosome in bacteria is circular whereas in eukaryotes it is linear.
Want to see the full answer?
Check out a sample textbook solutionChapter 12 Solutions
Genetics: From Genes to Genomes
- A cell undergoes several different steps as it divides into two identical daughter cells. This cell is undergoing cell division. In the step immediately following the phase that is shown, one daughter cell is missing a chromosome, and the other daughter cell has an extra chromosome. What happened in the step immediately before the phase pictured here to cause this problem? O A spindle fiber captured a chromosome on one side of the centromere, but a spindle fiber from the other centriole failed to capture it on the opposite side. O The cell plate formed prematurely and blocked chromosome movement, resulting in both chromosomes being trapped in just one daughter cell. O The cell moved prematurely from interphase to a non-dividing phase, and any unseparated chromosomes were prevented from dividing. O The centrosomes (and thus the aster) failed to form, preventing the cell from separating and redistributing chromosomes correctly into daughter cells.arrow_forwardIn the tracking chromosomal DNA movement through mitosis experiment, how many chromosomes did each of your daughter cells contain? Why is it important for each daughter cell to contain information identical to the parent cell? How often do human skin cells divide? Why might that be? Compare this rate to how frequently human neurons divide. What do you notice?arrow_forwardA crayfish strain became triploid while kept in a pet store. Pet owners released these crayfish into the wild, and they became an invasive species. These triploid animals have 2 different kinds of chromosomes (chromosome 1 and chromosome 2). To understand what kind of difficulties the crayfish triploid cells might have during the cell cycle you will draw: Cell is triploid with 2 different chromosomes ( 1 and 2) A) cell in G1 (assume chromosomes are condensed as they normally are in metaphase throughout the cell cycle) B) cell in G2 (assume chromosomes are condensed as they normally are in metaphase throughout the cell cycle) C) cell in Metaphase of mitosis D) cell in Metaphase I of the first meiotic division E) cell in Metaphase II of the second meiotic divisionarrow_forward
- The phases of mitosis are shown in Figure 6.4. Mitosis is the type of nuclear division that occurs when an animal or plant grows larger and when injury heals. Two daughter cells result because there is only one round of division, and it keeps the chromosome number constant (same as the parent cell). The prophase cell in Figure 6.4 has the same number of chromosomes as the telophase nuclei in Figure 6.4. Explain the different appearance of the chromosomes.arrow_forwardIn a dividing cell, the duplicated sets of chromosomes move along microtubules to opposite ends of the cell. How would you use an inhibitor to show that microtubules are essential for chromosome separation? What control treatment(s) would you use? What kind of cell junctions would you expect to find, and why, in a small animal where a chemical signal passes rapidly through cells to go from the head to the tail?arrow_forwarda. Manually, using a pencil, draw a cell in anaphase II from an organism in which 2n = 2 and each chromosome is metacentric. b. Given that each G1 nucleus from this organism contains 16 picograms of DNA, how many picograms of chromosomal DNA would you expect in the cell shown here?arrow_forward
- Hypothetically, a cell has DNA that weighs 10 picograms. This cell goes through S phase and is about to undergo mitosis. How much does the DNA of this cell weight now? How much would the DNA of the two cells produced at the end of mitosis weigh? Explain your reasoning.arrow_forwardThe term heterochromatin refers to heavily condensed regions of chromosomes that are largely devoid of genes. Since few genes exist there, these regions almost never decondense for transcription. At what point during the cell cycle would expect to observe decondensation of heterochromatic regions? Why?arrow_forwardFor below problem, consider a diploid cell that contains three pairs of chromosomes designated AA, BB, and CC. Each pair contains a maternal and a paternal member (e.g., Am and Ap). Using these designations, demonstrate your understanding of mitosis and meiosis by drawing chromatid combinations as requested. Be sure to indicate when chromatids are paired as a result of replication and/or synapsis. You may wish to use a large piece of brown manila wrapping paper or a cut-up paper grocery bag for this project and to work in partnership with another student. We recommend cooperative learning as an efficacious way to develop the skills you will need for solving the problems presented throughout this text. Question: Assume that each gamete resulting from Problem 29 fuses, in fertilization, with a normal haploid gamete. What combinations will result? What percentage of zygotes will be diploid, containing one paternal and one maternal member of each chromosome pair?arrow_forward
- The microscope image above shows the human chromosomes from a white blood cell. To create the image, researchers put cells in culture under conditions that encourage the cells to divide. They bathed the cells in a hypotonic (low salt) solution, which caused the cells to swell until their plasma membrane burst open. They "squashed" the chromosomes to spread them out, and stained them with a dye to make them visible under the microscope. Human chromosomes are numbered from longest (1) to shortest (22) plus the sex chromosomes X and Y. In the image chromosome 1 is about 7 micrometers. Answer the following questions. 1) What word(s) in the description above indicates that the chromosomes are not from a cell undergoing meiosis? 2) Based on the size, shape and appearance of the chromosomes in the image, in what cell cycle stage was the cell that the chromosomes came from? How can you tell? 3) Does the image suggest that centromere sequences are always located in the middle of a…arrow_forwardIn the absence of Separase, how would this affect the chromosomes dynamic during mitosis? Explain in detail. *arrow_forwardWhich of the following diagrams correctly depicts the orientation of microtubules during metaphase of mitosis? A B C OA I (-) (+) (+) (+) (+) (+) (+) (+) (+)50 (+) == (-) XX [(+) (-) E (-) J ++) (+) - (+) (-) (+) 11 15+ E (+) (-) 50 at &&05 (-) 50) (+) (-) (-) (+) (-) D E (+) (+) (+) D (-) St (+) coff (+) (-) (+) (+) (-) (-) (+) (-) (-) affere XXX (-)- (-) ++) (+) (-) (-) (-) (-) Karrow_forward
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningHuman Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning