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Into two daughter cells

Prokaryote cells divide and grow into two daughter cells. In the division process, the DNA replicates and each daughter cell receives one copy. [Pg.399]

Figure 7.3 The cell cycle Is Illustrated In this figure. Cell division proceeds through discrete phases Gj during which the cell grows and prepares for division the S phase where the DNA content and chromosomes double where the cell develops the structures needed for cell division and the M phase where the nucleus splits Into two and the cell divides Into two daughter cells. Figure 7.3 The cell cycle Is Illustrated In this figure. Cell division proceeds through discrete phases Gj during which the cell grows and prepares for division the S phase where the DNA content and chromosomes double where the cell develops the structures needed for cell division and the M phase where the nucleus splits Into two and the cell divides Into two daughter cells.
Growth is essential during development, as a baby matures into an adult, and is also required in the maintenance and repair of an adult s tissues. Cells make new tissue by growing and dividing—a cell divides into two daughter cells, which generally have the same properties as the original cell. Division continues until the needed tissue is complete. [Pg.58]

The cell cycle consists of a presynthetic phase (Gj), which precedes DNA synthesis, the phase of DNA synthesis (S), an interval that follows DNA synthesis (G2), and mitosis (M), during which the G2 cell with a double complement of DNA divides into two daughter cells. Each of these daughter cells may then immediately reenter the division cycle at Gj or pass into a nonproliferative state (G0) for an indefinite period of time. As the length of the cell cycle increases, the duration of the G phase increases, whereas the durations of the S, G2, and M phases remain relatively constant. [Pg.118]

The cell cycle in eukaryotes is divided into four phases, Glt S. G2, and M (Fig. 16-4). The cycle starts at the beginning of G, (G = gap), which often constitutes the major phase in duration. DNA replication commences at the beginning of the S phase and is completed before entry into G2. Mitosis, or the M phase, is relatively short and includes those steps that lead to chromosome segregation and partitioning into two daughter cells. [Pg.461]

In gap phases Gi and G2, the cell is preparing for DNA replication and cell division respectively. M phase is composed of two discrete steps mitosis, which constitutes the pairing and separation of the duplicated chromosomes, and cytokinesis, the physical process whereby the cell splits into two daughter cells. Not all cells continue to divide during the life span of an... [Pg.299]

Once in every turn of the cycle, the cell divides and splits into two daughter cells. The duplicated chromosomes must be separated with perfect precision. Moreover, all of... [Pg.226]

It is clear from observing chromosome movements that cell division occurs in an ordered sequence of events (Fig. la). First chromosomes attach to spindle microtubule fibers and move to the spindle equator. Only after completion of this step do sister chromosomes separate at anaphase and move to opposite sides of the cell, followed by their division into two daughter cells. Events must occur in this order for successful chromosome segregation. If the cell enters anaphase prematurely, before chromosomes have attached properly to the spindle, the sister chromosomes will not segregate equally, which leads to aneu-ploid daughter cells. Therefore, mechanisms that determine the timing of anaphase onset are critical for the success of mitosis. [Pg.188]

As noted in Section 2, Metz and Diekmann [MD, p. 237] describe a different size-structured model, one that reflects the cell-division process quite well. They assume that cell size x varies among the individual cells of the population, from a minimum value Xmin to a maximum value that is normalized to 1. A function b x) gives the per-unit time probability of a cell of size x dividing. Small cells are not allowed to divide (f>(Ar) = 0, xmother cell of size x is assumed to divide into two daughter cells, one of size px and one of size (1 -p)x, with probability d p), 0 < / < 1. Of course, d(p) = d l —p) and/o d(p) dp =. The unit of size x -whether length, area, or volume - is not specified in [MDj. This makes their assumption that the growth rate of a cell of size x is proportional to X (and to f(S)) subject to different interpretations. The reader is referred to [MD, p. 238] for the equations and hypotheses. Their model also can be reduced to the equations considered in Chapter 1. [Pg.229]

Prior to cell division, the nucleus replicates itself so that the two new cells will each contain genetic information. Several nuclear enzymes coordinate the replication of DNA. During cell division, the nuclear envelope breaks down, and equal copies of DNA and cytoplasm are partitioned into two daughter cells. After division, the nuclear envelopes reform in each daughter cell around its own copy of DNA. This fundamental sequence of events allows for the continuation of eukaryotic life during embryonic development and cellular regeneration throughout life. [Pg.607]

The cascade is shown in Figure 6-12. A further feature of the pluripoteni stem cell deserves mention. Each stem cell divides into two daughter cells, one an active hematopoietic progenitor and one quiescent. The active precursor matures to give hematopoietic progenitors and then circulating blood cells. The quiescent stem cells rejoin the stem cell pool. Hence, the number of parental cells i.s always the same. This process is termed self-renewal. [Pg.177]

As discussed in Section III.B, we start from consideration of a prototype of cell, consisting of molecules that catalyze each other. As the reaction progresses, the number of molecules in this protocell will increase. Then, this cell will be divided when its volume (the total number of molecules) is beyond some threshold. Then the molecules split into two daughter cells. Then our question in Section I is restated as follows How are the chemical compositions transferred to the offspring cells Do some specific molecules start to carry heredity in the sense of control and preservation, so that the reproduction continues ... [Pg.557]

Here, we propose a kinetic model of the relationship between a and Nt/N0 in Figure 35.9. Assuming that only the mES cell with high activity is capable of cell proliferation and divides into two daughter cells once in 25 h and that the mES cell with a low activity, on the other hand, is going to die without cell division, the increasing ratio of cellular population from 0 to 25 h is given as follows ... [Pg.416]

For localized protein complexes to be differentially incorporated into two daughter cells requires that the plane of cell division be appropriately oriented. In dividing fly neuroblasts, the mitotic spindle first aligns perpendicular to the apical-basal axis and then turns 90 degrees to align with it at the same time that the basal complexes become localized to... [Pg.923]

The cellular structure is dynamic. The most dramatic changes occur when a cell divides into two daughter cells as part of the process of cell proliferation. Cell division in eukaryotes involves the process of mitosis in which the nuclear membrane dissolves, the chromosomes condense and separate into two groups, and two nuclear membranes reassemble around the chromosomes. Finally, in the process of cytokinesis, the cell membrane contracts in the middle to form a shape like the character "8" and the two halves separate to form independent cells. Although it is the most dramatic of the microscopically visible events, the division itself is just part of a complete cycle of molecular events in which the cell prepares for division and then carries it out (Fig. 1.3). [Pg.50]

If an individual cel is observed it will be seen to increase in size and eventually divide into, two daughter cells, each of which will grow and later divide. The time between one cell division and the next is the generation time, and varies very widely for a given type of cell. The mean generation time is the mean time for all the cells in a given culture, under the particular conditions of the experiment. [Pg.454]

Bacteria normally divide and reproduce by asexual reproduction in a process called binary fission. Bacteria are prokaryotes, and, as such are relatively simple BU. They carry most of their genes on a single chromosome attached to the plasma membrane. When a single bacterial ceU divides, it first replicates its chromosome and attaches it to a different membrane site. When the bacterium has grown to about twice its normal size, the plasma membrane grows inward between the two chromosomes and divides the parent ceU into two daughter cells, each with a complete genome. [Pg.381]

Mother cell A cell that has approximately doubled in size and is about to divide into two daughter cells. [Pg.1158]

The best known example of an alkaloid which inhibits ceU division in plants is colchicine. Added in minute amounts, this alkaloid interferes with the formation of the cell carokinetic spindle instead of a division of the cell into two daughter cells, a restitutive cell is formed with a doubled set of chromosomes. The alkaloid, while very active on cells of most species of plants, produces no effects in Colchicum autumnale, the most common source of this compound. Alkaloids of Senecio and Crotalaria can cause chromosome breakage in a number of organisms, mostly animals, but are... [Pg.144]

A septum is formed in the middle of the cell as a result of the synthesis of portions of the membrane and the cell wall. It separates the mother cell little by little into two daughter cells. The genetic material and the other cellular components are simultaneously distributed between them. Finally, when the septum is completely formed, the two daughter cells separate. Cell and nucleus division are not synchronous replication is quicker. Moreover, a replication cycle can start before cell division is... [Pg.122]

In accordance with experimental observations, the model assumes that cells migrate by executing persistent random walks [49,121,122] as they go through their division cycle. In a uniform environment, the direction after each turn is randomly selected. However, cell movement can be biased to simulate chemotaxis or haptotaxis. If the cell does not collide with another cell, this persistent random movement continues until the end of the cell s current division cycle upon which the cell stops and divides into two daughter cells. Cell division is asynchronous and the distribution of cell division time tj is a measurable characteristic of each cell phenotype. [Pg.518]


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Daughter cells

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