Concept explainers
Figure 10.6 Which of the following is the correct order of events in mitosis?
- Sister chromatids line up at the metaphase plate. The kinetochore becomes attached to the mitotic spindle. The nucleus reforms and the cell divides. Cohesin proteins break down and the sister chromatids separate.
- The kinetochore becomes attached to the mitotic spindle. Cohesin proteins break down and the sister chromatids separate. Sister chromatids line up at the metaphase plate. The nucleus reforms and the cell divides.
- The kinetochore becomes attached to the cohesin proteins. Sister chromatids line up at the metaphase plate. The kinetochore breaks down and the sister chromatids separate. The nucleus reforms and the cell divides.
- The kinetochore becomes attached to the mitotic spindle. Sister chromatids line up at the metaphase plate. Cohesin proteins break down and the sister chromatids separate. The nucleus reforms and the cell divides.
Introduction:
The mitosis is the process of the cell division, which occurs in all the somatic cells present in the body of the multicellular organism. The mitosis is divided into four phases, prophase, metaphase, anaphase and telophase.
In the prophase stage, the genetic material condenses to form the chromatids, these chromatids get lined up at the equator or the metaphase plate during metaphase and the spindle fibers bind to the kinetochore present at the center of the sister chromatids. In anaphase, the sister chromatids are pulled to the opposite poles and in telophase, the chromatids decondensed and nuclear envelope is formed, resulting in two nuclei in the dividing cell.
Answer to Problem 1VCQ
Correct answer:
The correct answer is option (d) The kinetochore becomes attached to the mitotic spindle. Sister chromatids line up at the metaphase plate. Cohesin proteins break down and the sister chromatids separate. The nucleus reforms and the cell divides.
Explanation of Solution
Explanation/justification for the correct answer:
Option (d): during early metaphase, the kinetochore attaches to the spindle fibers. The sister chromatids of the dividing cells line up at the metaphase plate, after the alignment, the spindle fibers attach to the kinetochore. The sister chromatids are bind together with the help of cohesin. After the alignment of the sister chromatids at the metaphase plate, the cohesin breaks and the sister chromatid separate and move to the opposite poles. A nucleus is formed on each opposite pole and then the cytoplasmic division results in the formation of two new cells.
Explanation for the incorrect answer:
Option (a): In this option, the separation of sister chromatids is placed after the formation of a nucleus, but the formation of the nucleus takes place after the sister chromatids are separated and move to opposite poles. So, it is an incorrect option.
Option (b): In this option, the separation of the sister chromatids is placed before the lining of the sister chromatids on the metaphase plate. The cohesin protein breaks after the sister chromatids are lined up on the metaphase plate, which causes the breaking of the sister chromatids. So, it is an incorrect option.
Option (c): In this option, it is said that the kinetochore is attached to the cohesin protein, but the kinetochore actually gets attached to the spindle fibers. So, it is an incorrect answer.
During metaphase, the mitotic spindle binds to the kinetochore and causes the alignment of sister chromatids on metaphase plate and the cohesin breaks resulting in separation of the sister chromatids. The sister chromatids are then pulled to the opposite pole, there the new nucleus is formed followed by cytokinesis and in this way; two new cells from one existing cell are formed. Hence, option (d) is the correct answer.
Want to see more full solutions like this?
Chapter 10 Solutions
Biology 2e
Additional Science Textbook Solutions
College Physics
Microbiology: An Introduction
Campbell Essential Biology with Physiology (6th Edition)
Human Biology: Concepts and Current Issues
Genetic Analysis: An Integrated Approach (2nd Edition)
- In the cell cycle, at which stages do two chromatids make up one chromosome? a. beginning of mitosis b. end of G1 c. beginning of S d. end of mitosis e. beginning of G2arrow_forwardFigure 6.4 Which of the following is the correct order of events in mitosis? a. Sister chromatids line up at the metaphase plate. The kinetochore becomes attached to the initotic spindle. The nucleus re-forms and the cell divides. The sister chromatids separate. b. The kinetochore becomes attached to the mitotic spindle. The sister chromatids separate. Sister chromatids line up at the metaphase plate. The nucleus re-forms and the cell divides. c. The kinetochore becomes attached to metaphase plate. Sister chromatids line up at the metaphase plate. The kinetochore breaks down and the sister chromatids separate. The nucleus re-forms and the cell divides. d. The kinetochore becomes attached to the mitotic spindle. Sister chromatids line up at the metaphase plate. The kinetochore breaks apart and the sister chromatids separate. The nucleus re-forms and the cell divides.arrow_forwardAfter mitosis, each daughter cell contains genetic instructions that are ______ and _____ chromosome number of the parent cell. a. identical to the parent cells; the same b. identical to the parent cells; one-half the c. rearranged; the same d. rearranged; one-half thearrow_forward
- S. Chromosomes are duplicated during what stage of the cell cycle? G1 phase S phase prophase prometaphasearrow_forwardAll of the following are stages of mitosis except _________. a. prophase b. interphase c. metaphase d. anaphasearrow_forwardWhich of these is occurring during the mitotic step shown here? The nuclear membrane breaks down. The sister chromatids line up at the center of the cell. The chromosomes begin to uncoil as the nuclear membrane reassembles around them. Cytoplasm is divided into the two daughter cells. The sister chromatid pairs are pulled apart by the spindle fibers.arrow_forward
- The centromeric connections between chromatids fail to be severed. Kinetochores from sister chromatids become attached to microtubules from the same pole. A motor protein at the kinetochore is not functional. The chromosomes fail to attach to the kinetochore microtubules. Chromosomes will not move to the metaphase plate. Chromatids will not separate during anaphase. One kinetochore will detach from the spindle. Chromosomes will not move toward centrosome during prometaphase.arrow_forwardWhat is the fundamental difference between mitosis and meiosis? Be sure to include the following: types of cells produced by each process (haploid or diploid) (body cells or sex cells) types of cells that undergo each process stages involved in each process number of times the DNA is replicated number of divisions involved in each processarrow_forwardWhich of the following is NOT correct answer about telophase of mitosis: The mitotic spindle is formed in this phase Two new nuclei form, and two sets of chromosomes Nuclear membrane and nucleoid reappear in this phase The enzyme aminoacyl TRNA synthetase charges the TRNA molecules with the correct amino acids FRNA molecules with the correct amino acids MRNA molecules with the correct amino acidsarrow_forward
- Which of the following statements are true regarding mitosis in humans? 23 pairs of homologous chromosomes are separated four haploid gametes are produced in males 46 pairs of homologous chromosomes are separated two genetically identical daughter cells are produced 23 pairs of sister chromatids are separated 46pairs of sister chromatids are separated 1 haploid gamete and 2 polar bodies are produced in femalesarrow_forwardPut the following phases of the cell cycle and mitosis in the correct order. Prometaphase Interphase - S phase Telophase Prophase Anaphase Interphase - G1 Metaphase Interphase - G2arrow_forwardNormal events in mitosis gives rise to daughter cells with exactly the same chromosome number and genetic material. What may be expected to happen chromosomally and genetically to: an unfertilized egg that undergoes mitosis, but fails to undergo cytokinesis? a cell with a chromosome that lost its centromere? a cell with a chromosome that contains two centromeres?arrow_forward
- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxConcepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax CollegeHuman Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage Learning
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning