What is the proper sequence in mitosis?
Mitosis consists of four basic phases: prophase, metaphase, anaphase, and telophase. These phases occur in this strict sequential order, and cytokinesis - the process of dividing the cell contents to make two new cells - starts in anaphase or telophase.
1. Prophase - During prophase, chromosomes get visible (chromatids), the centrioles migrate to the poles, nuclear membrane and nucleolus disappear and spindle formation is seen. Prophase in mitosis is longer than any other phases of mitosis because the cell has to prepare for the actual division that takes place from early through late prophase.
2. Metaphase - During this, chromosomes lineup around the centre (Cells in metaphase have the chromosomes, which appear as long thin strands under the microscope).
3. Anaphase - here, chromatids separate and move to opposite poles by spindle fibers. This allows each daughter cell to have an identical copy of each of the original cell’s chromosomes.
4.Telophase - During this phase, chromosomes disappear (become chromatin), nuclear membrane reforms, nucleoli reappears, spindle disappears and centrioles duplicate.
The correct answer is option D.
Which of the phases of mitosis is the longest?
Prophase is the longest phase of mitosis. This phase separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells.
In a cell cycle, during which phase are chromosomes arranged on the equatorial plate?
During metaphase, the chromosomes get arranged in the form of a plate called the equatorial plate or metaphase plate at the equator of the spindle. This plate is at right angles to the axis of the spindle and is formed of the kinetochores, the arms of chromatids trailing away. The centromeres are drawn to the equator by the equal pull of two chromosomal fibres which connect the sister kinetochores to the opposite poles. The process of drawing the chromosomes onto the equator of the spindle is known as congression.
How many mitotic divisions are needed for a single cell to make 128 cells?
A single mitotic division results in the production of two cells from single cell
Centromere is required for
The centromere is the part of the chromosomes where the two sister chromatids are attached. It is required for movement of chromosomes towards poles. During mitosis, spindle fibers attach to the centromere via the kinetochore. Their physical role is to act as the site of assembly of the kinetochore - a highly complex multiprotein structure that is responsible for the actual events of chromosome segregation i.e., binding microtubules and signalling to the cell cycle machinery when all chromosomes have adopted correct attachments to the spindle, so that it is safe for cell division to proceed to completion and for cells to enter anaphase.
So, the correct answer is option C.
At which stage of mitosis do chromatids separate and pass to different poles?
The paired chromosomes (sister chromatids) separate and begin moving to opposite ends (poles) of the cell. Spindle fibers not connected to chromatids lengthen and elongate the cell. At the end of anaphase, each pole contains a complete compilation of chromosomes.
Cell division is initiated in plants by
Mitosis is the mechanism by which the chromosome content of a somatic cell (haploid or diploid) is kept constant through successive cell divisions. The division of the cell is initiated by division of the nucleus i.e. Karyokinesis followed by division of cytoplasm i.e. Cytokinesis.
A cell plate is laid during
Cytokinesis is the part of the cell division process during which the cytoplasm of a single eukaryotic cell divides into two daughter cells. Cytoplasmic division begins during or after the late stages of nuclear division in mitosis and meiosis. During cytokinesis the spindle apparatus partitions and transports duplicated chromatids into the cytoplasm of the separating daughter cells. It thereby ensures that chromosome number and complement are maintained from one generation to the next and that, except in special cases, the daughter cells will be functional copies of the parent cell. After the completion of the telophase and cytokinesis, each daughter cell enters the interphase of the cell cycle.
In mitosis, the number of chromosome sets in daughter cells will be
Same as parents because it is a equational division.
Which stages of cell division do the figures A and B represent?
In Fig.1 cromatid are moving to opposite pole i.e Late anaphase.
In Fig.2 all organelles are present i.e prophase.