Search results
Results From The WOW.Com Content Network
The first frog egg extract was reported in 1983 by Lohka and Masui. [1] This pioneering work used eggs of the Northern leopard frog Rana pipiens to prepare an extract. Later, the same procedure was applied to eggs of Xenopus laevis, becoming popular for studying cell cycle progression and cell cycle-dependent cellular events. [2]
Mitosis (/ m aɪ ˈ t oʊ s ɪ s /) is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division by mitosis is an equational division which gives rise to genetically identical cells in which the total number of chromosomes is maintained. [1]
These chromosomes, carrying genetic information, align in the equator of the cell between the spindle poles at the metaphase plate, before being separated into each of the two daughter nuclei. This alignment marks the beginning of metaphase. [2] Metaphase accounts for approximately 4% of the cell cycle's duration. [citation needed]
The cell cycle is a series of complex, ordered, sequential events that control how a single cell divides into two cells, and involves several different phases. The phases include the G1 and G2 phases, DNA replication or S phase, and the actual process of cell division, mitosis or M phase. [1]
Cell synchronization is a process by which cells in a culture at different stages of the cell cycle are brought to the same phase. Cell synchrony is a vital process in the study of cells progressing through the cell cycle as it allows population-wide data to be collected rather than relying solely on single-cell experiments.
While the video claims that this is the first time in history this experiment has been done, The Daily Mail says that a similar process was outlined in a chapter of a US biology textbook from 1993.
G 1 phase is the first of the four phases of the cell cycle, and is part of interphase. While in G 1 the cell synthesizes messenger RNA (mRNA) and proteins in preparation for subsequent steps of interphase leading to mitosis. In human somatic cells, the cell cycle lasts about 18 hours, and the G 1 phase makes up about 1 / 3 of that time. [13]
There are two popular and overlapping theories that explain the origins of crossing-over, coming from the different theories on the origin of meiosis.The first theory rests upon the idea that meiosis evolved as another method of DNA repair, and thus crossing-over is a novel way to replace possibly damaged sections of DNA. [9]