A cell is the smallest structural and functional unit of an organism. A cell is typically microscopic and consists of cytoplasm, a nucleus and enclosed in a membrane. For the information, a cell also has reproduction same like human, animal and plant. Due to Rudolf Virchow (1855), a German physician said that “Where a cell exists, there must have been a pre-existing cell, just as the animal arises only from an animal and the plant only from a plant”. He can be concluded that this concept with the Latin axiom “Omnis cellula e cellula,” that means “Every cell from a cell”. It shows that the continuing life of the cell by doing the cell reproduction. To make the cell do the reproduction, the cell must have to do the division. To make the division occur, it needs to through a certain process or sequence that we call the cell cycle. Based on the Ching et al. (2011) the cell cycle is the sequence of stages that the cell to pass through between one cell division and the next. According to Reece, Urry, Cain, Wasserman, Minorsky and Jackson (2011) in the cell cycle it divided into three phases: the G1 phase (“first gap”), the S phase (“synthesis”), and the G2 phase (“second gap”). The period between mitotic division, which are a G1, S and G2 are called interphase. After three phases done it will through mitosis and cytokinesis. It was included in the mitotic phase (M phase) which the shortest part of the cell cycle. Mitosis is the process which will be divided a cell by replicates and divides the original chromosomes to obtain two new cells. These two cells will identical to original one. According to Karp (1999), mitosis is the most metabolic activities of the cell, including transcription and translation, are curtailed, and the cell beco...
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Appendix 1
Figure 1. The Mitosis
Cell cycle events portray some differences between different living things. In all the three living things, their cells divide, a process referred to as mitosis. The mitosis stage differs and it encompasses four phases. During development, the cell cycle functions endlessly with newly created daughter cells directly embarking on their path to mitosis. Bacteria cells separate forming two cells after every thirty minutes under favorable conditions. However, the eukaryotic cells take quite longer compared to bacteria cells to develop and divide. Nevertheless, in both animals and plants, cell cycle is usually highly regulated to prevent imbalanced and excessive growth. Both animals and plants are known as eukaryotes meaning that their DNA exists inside their cells’ nuclei. Therefore, their cells as well as mitotic processes are similar in various ways (Eckardt, 2012).
Each cell contains the same genetic code as the parent cell, it is able to do this because it has copied it’s own chromosomes prior to cell death. division. The. Meiosis consists of two divisions whilst mitosis is followed. in one division; both these processes involve the stages of interphase, prophase, metaphase, anaphase, and telophase.
As part of the cell cycle, mitosis is the nuclear division of replicated chromosomes by the disconnection of the replicated chromosomes to form two genetically identical daughter nuclei. Escorted by mitosis is commonly the process of cytokinesis. The cytokinesis process entails a dividing cell splitting into two, resulting in the subdivision of the cytoplasm into two cellular suites.
Mitosis is the process by which the cell replicates itself and is left with two exact cells.
When it comes to the topic of cancer, it is one of the most deadly diseases someone can ever contract. Cancer occurs when the cells divide and spread uncontrollably in the body creating clusters that have no space to go and eventually create a tumor (a swelling of a part of the body, generally without inflammation, caused by an abnormal growth of tissue, whether benign or malignant) that needs to be removed surgically. Depending on whether the procedure is successful or not, if it is, we can use a remedy for accelerated cell reproduction. Accelerated cell reproduction is the process of increasing and improving the reproduction and regenerative rate of cells so that they can perform the task of replacing lost or damaged cells, wounds, scrapes, healing scars, etc. As one uses snake venom to cure a snake bite, one can also use an acceleration of cell reproduction to cure cancer which involves cells accelerating and going in the wrong direction. People wonder why we have such terrible diseases such as cancer still abroad. It is because accelerated cell reproduction has not been put into effect. If it gets put into effect then we will have a starting point in our research to success. This will be the beginning of a new era if such a phenomenon were to place.
Precise chromosomal DNA replication during S phase of the cell cycle is a crucial factor in the proper maintenance of the genome from generation to generation. The current “once-per-cell-cycle” model of eukaryotic chromosome duplication describes a highly coordinated process by which temporally regulated replicon clusters are sequentially activated and subsequently united to form two semi-conserved copies of the genome. Replicon clusters, or replication domains, are comprised of individual replication units that are synchronously activated at predetermined points during S phase. Bi-directional replication within each replicon is initiated at periodic AT-rich origins along each chromosome. Origins are not characterized by any specific nucleotide sequence, but rather the spatial arrangement of origin replication complexes (ORCs). Given the duration of the S phase and replication fork rate, adjacent origins must be appropriately spaced to ensure the complete replication of each replicon. Chromatin arrangement by the nuclear matrix may be the underpinning factor responsible for ORC positioning. The six subunit ORC binds to origins of replication in an ATP-dependent manner during late telophase and early G1. In yeast, each replication domain simply contains a single ORC binding site. However, more complex origins are characterized by an initiation zone where DNA synthesis may begin at numerous locations. A single round of DNA synthesis at each activated origin is achieved by “lic...
The cell cycle is the process by which cells progress and divide. In normal cells, the cell cycle is controlled by a complex series of signaling pathways by which a cell grows, replicates it’s DNA and divides, these are called proto-oncogenes. A proto-oncogene is a normal gene that could become an oncogene due to mutations. This process has mechanisms to ensure that errors are corrected, if they are not, the cells commit suicide (apoptosis). This process is tightly regulated by the genes within a cell’s nucleus. In cancer, as a result of genetic mutations, this process malfunctions, resulting in uncontrolled cell proliferation. Mutations in proto-oncogene or in a tumour suppressor gene allow a cancerous cell to grow and divide without the normal control imposed by the cell cycle. A change in the DNA sequence of the proto-oncogene gives rise to an oncogene, which
The cell cycle is the synchronous process by which existing cells give rise to new cells. This process can be broadly divided into two stages: interphase and mitosis. During interphase, cells increase in size, replicate their chromosomes to form sister chromatids, and increase their rates of protein synthesis. During mitosis, sister chromatids are separated and transported to opposite cell poles, followed by cell division (cytokinesis). Recent investigations have revealed much information about the morphological changes that occur in mitotic cells. These morphological changes occur in a precise order and include, in chronological order, condensation of chromosomes, changes in microtubule assembly patterns, nuclear envelope breakdown, chromosome alignment at the center of the cell, chromosome separation to opposite cell poles, and nuclear envelope reassembly prior to cytokinesis. Similar morphological changes have been observed during meiosis, indicating that the processes driving DNA distribution in somatic cells and gametes is similar (Baserga, 1968).
Each of the cells have precisely half the number of chromosomes from the original cell. There are many different processes go in this phase so the cell has time to prepare for the second part of meiosis. The only persistent thing is that genetic material does not copy, but in its place it continues to get divided. The next stage is prophase 2 during this phase the chromosomes start traveling to the metaphase plate again, which is at the midpoint of the cell. The next stage is metaphase 2 the chromosomes line up along the center of the cell before it breaks up into two. Then the chromatids point towards the opposite ends of the cell. The next stage is anaphase 2. This is the second to last phase in meiosis and it has many events that happen. The first event is when the sister chromatids separate and move towards the opposite ends of the pole. When this is happening the spindle fibers will lengthen and make the cell bigger. Then the paired chromatids will begin to detach from each other. Now every chromatid pair is considered to be a full chromosome. Now anaphase 2 will start getting ready for the final phase of meiosis. Both cell poles start to move even more apart and now it can be seen as splitting. By the end of this phase each pole
The cell is the fundamental structural unit of all living organisms. Some cells are complete organisms, such as the unicellular bacteria and protozoa; others, such as nerve, liver, and muscle cells, are specialized components of multi-cellular organisms. Cells range in size from the smallest bacteria-like mycoplasmas, which are 0.1 micrometer in diameter, to the egg yolks of ostriches, which are about 8 cm (about 3 in) in diameter. Although they may differ widely in appearance and function, all cells have a surrounding membrane and an internal, water-rich substance called the cytoplasm, the composition of which differs significantly from the external environment of the cell. Within the cell is genetic material, deoxyribonucleic acid (DNA), containing coded instructions for the behavior and reproduction of the cell and also the chemical machinery for the translation of these instructions into the manufacture of proteins. Viruses are not considered cells because they lack this translation machinery; they must parasitize cells in order to translate their own genetic code and reproduce themselves.
The process of cell division plays a very important role in the everyday life of human beings as well as all living organisms. If we did not have cell division, all living organisms would cease to reproduce and eventually perish because of it. Within cell division, there are some key roles that are known as nuclear division and cytokinesis. There are two types within nuclear division. Those two types being mitosis and meiosis. Mitosis and meiosis play a very important role in the everyday life as well. Mitosis is the asexual reproduction in which two cells divide in two in order to make duplicate cells. The cells have an equal number of chromosomes which will result in diploid cells. Mitosis is genetically identical and occurs in all living
The merger of two germinal cells, one being a sperm cell and the other being an egg cell, is complete within twelve hours, at which time the egg is fertilized and becomes a zygote containing forty six chromosomes required to create a new human life. It is during this remarkable process when conception occurs. Conception confirms life and makes that undeveloped human one of a kind (Rorvik & Shettles, 1983, p. 16). Many researchers, as well as scientists, identify the first moments of life as the instant when a sperm cell unites with an ovum, o...
Meiosis is a specialized form of nuclear division in which there two successive nuclear divisions (meiosis I and II) without any chromosome replication between them. Each division can be divided into 4 phases similar to those of mitosis (pro-, meta-, ana- and telophase). Meiosis occurs during the formation of gametes in animals.
This report provides an insight into the differences in the structure of cells and the way that they carry out their internal mechanisms. Cells form the basis of all living things and they are the smallest single unit of life. Cell biology is the study of cells and how they function, from the subcellular processes which keep them functioning, to the
What is the cell cycle? It’s the way we reproduce. A series of events lead up from the beginning that which gives them life to the splitting of cells, The separate steps make up this very important process. Without the division of cells, we simply would not be here today.