![]() ![]() This occurs, in fact, in a large number of higher organisms during meiosis-the process by which sex cells ( gametes) are formed: originally each chromosome of the cell is in a pair ( diploid) during meiosis these diploid pairs of chromosomes are separated so that each sex cell has only one of each pair of chromosomes ( haploid). In some instances of binary fission, there may be an unequal cytoplasmic division with an equal division of the chromosomes. The nucleus then divides, one of the daughter nuclei passes into the bud, and ultimately the two cells separate. In these fungi the cell wall forms a bubble that becomes engorged with cytoplasm until it is ultimately the size of the original cell. Budding yeast cells provide an interesting exception. In the hard-walled cells of higher plants, a median plate forms and divides the mother cell into two compartments in animal cells, which do not have a hard wall, a delicate membrane pinches the cell in two, much like the separation of two liquid drops. In higher organisms ( eukaryotes) there is first an elaborate duplication and then a separation of the chromosomes ( mitosis), after which the cytoplasm divides in two. In bacteria ( prokaryotes) the chromosome (the body that contains the DNA and associated proteins) replicates and then divides in two, after which a cell wall forms across the elongated parent cell. Of the various kinds of cell division, the most common mode is binary fission, the division of a cell into two separate and similar parts. SpaceNext50 Britannica presents SpaceNext50, From the race to the Moon to space stewardship, we explore a wide range of subjects that feed our curiosity about space!.Learn about the major environmental problems facing our planet and what can be done about them! Saving Earth Britannica Presents Earth’s To-Do List for the 21st Century.100 Women Britannica celebrates the centennial of the Nineteenth Amendment, highlighting suffragists and history-making politicians.COVID-19 Portal While this global health crisis continues to evolve, it can be useful to look to past pandemics to better understand how to respond today.Student Portal Britannica is the ultimate student resource for key school subjects like history, government, literature, and more.This Time in History In these videos, find out what happened this month (or any month!) in history.#WTFact Videos In #WTFact Britannica shares some of the most bizarre facts we can find.Demystified Videos In Demystified, Britannica has all the answers to your burning questions.Britannica Classics Check out these retro videos from Encyclopedia Britannica’s archives.Britannica Explains In these videos, Britannica explains a variety of topics and answers frequently asked questions. ![]()
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