Anaphase II: The sister chromatids are then pulled to opposite poles due to the action of the meiotic spindle. The separated chromatids are now individual chromosomes. Telophase II and cytokinesis: The chromosomes complete their move to the opposite poles of the cell. A membrane forms around each set of chromosomes to create two new cell nuclei. This is the last phase of meiosis, however cell division is not complete without another round of cytokinesis.
Once cytokinesis is complete there are four granddaughter cells, each with half a set of chromosomes haploid : in males, these four cells are all sperm cells in females, one of the cells is an egg cell while the other three are polar bodies small cells that do not develop into eggs. Related Content:. What is a cell? What is a chromosome? What is mitosis? What is DNA? Mitosis versus meiosis. What is a genetic disorder? How helpful was this page?
What's the main reason for your rating? Which of these best describes your occupation? What is the first part of your school's postcode? How has the site influenced you or others? During both meiosis I and meiosis II, cells undergo the same phases found in mitosis, but the processes and results are different.
Within meiosis I, homologous chromosomes become paired and crossing over occurs. Homologous pairs are separated, and the two resulting daughter cells have half as many chromosomes per cell. As previously mentioned, the first round of nuclear division that occurs during the formation of gametes is called meiosis I. It is also known as the reduction division because it results in cells that have half the number of chromosomes as the parent cell.
During prophase I , the chromosomes condense and become visible inside the nucleus. Because each chromosome was duplicated during the S phase that occurred just before prophase I, each now consists of two sister chromatids joined at the centromere. This arrangement means that each chromosome has the shape of an X. Once this chromosomal condensation has occurred, the members of each chromosome pair called homologous chromosomes , because they are similar in size and contain similar genes , align next to each other.
At this point, the two chromosomes in each pair become tightly associated with each other along their lengths in a process called synapsis. Then, while the homologous chromosomes are tightly paired, the members of each pair trade adjacent bits of DNA in a process called crossing over , also known as recombination Figure 1.
This trading of genetic material creates unique chromosomes that contain new combinations of alleles. During meiosis II , the two cells once again cycle through four phases of division. Meiosis II is sometimes referred to as an equational division because it does not reduce chromosome number in the daughter cells — rather, the daughter cells that result from meiosis II have the same number of chromosomes as the "parent" cells that enter meiosis II.
Remember, these "parent" cells already have half the number of chromosomes of the original parent cell thanks to meiosis I. This page appears in the following eBook. Aa Aa Aa. What happens during meiosis I?
Prophase I. Figure 1: Recombination is the exchange of genetic material between homologous chromosomes. At the end of prophase I, the nuclear membrane finally begins to break down. Outside the nucleus, the spindle grows out from centrosomes on each side of the cell.
As in mitosis, the microtubules of the spindle are responsible for moving and arranging the chromosomes during division. Metaphase I. Figure 2: Near the end of metaphase I, the homologous chromosomes align on the metaphase plate. Each chromosome looks like an elongated X-shaped structure. In the pair of chromosomes at top, the chromosome at left is mostly green, but the lower region of the right chromatid is orange. The chromosome at right is mostly orange, but the lower region of the left chromatid is green.
A second pair of chromosomes exhibiting the same pattern of coloration on their arms is shown below the topmost pair. Mitotic spindles are located at each side of the cell.
Each spindle apparatus is composed of several white lines, representing fibers, emanating from two oval-shaped structures, representing centrosomes. The fibers attach the centrosomes to the centromeres of each chromosome.
Shorter fibers also emanate from the mitotic spindle but are not attached to chromosomes. At the start of metaphase I , microtubules emerge from the spindle and attach to the kinetochore near the centromere of each chromosome.
Daughter Cells and Cancer. Regina Bailey. Biology Expert. Regina Bailey is a board-certified registered nurse, science writer and educator. Updated February 10, Key Takeaways Daughter cells are cells that are the result of a single dividing parent cell.
Two daughter cells are the final result from the mitotic process while four cells are the final result from the meiotic process. For organisms that reproduce via sexual reproduction, daughter cells result from meiosis.
It is a two-part cell division process that ultimately produces an organism's gametes. At the end of this process, the result is four haploid cells. Cells have an error-checking and correcting process that helps to ensure the proper regulation of mitosis. If errors occur, cancerous cells that continue to divide may be the result. Featured Video.
Cite this Article Format. Bailey, Regina. Daughter Cells in Mitosis and Meiosis. A Genetics Definition of Homologous Chromosomes. Centromere and Chromosome Segregation. The Stages of Mitosis and Cell Division. Biology Prefixes and Suffixes: diplo-. An Introduction to Male and Female Gonads. Frequently Asked Biology Questions and Answers. Your Privacy Rights. To change or withdraw your consent choices for ThoughtCo.
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