Write an essay explaining the continuity of life and how it is based on heritable information in the form of DNA and its transmission from one generation to another.
Life's continuity is based on the unremitting passage of inherited information that takes the form of DNA. This essay extensively examines the fundamental processes that allow for the transmission of DNA and thus life. It initially identifies how information essential for life is stored in DNA and then explains the processes of DNA replication, Mitosis and Meiosis. It goes on to discuss the differences between continuity of life in Prokaryotes and Eukaryotes, describing the various advantages and disadvantages of both sexual and asexual reproduction. It highlights the benefits of genetic variation in ensuring life’s diversity and finally concludes with the argument that DNA is essential for the continuity of life. The reason why DNA is exceedingly important is because it provides the information needed for life and a way of passing this information along. It at the same time can allow for genetic diversity which ensures life can be best suited to different changing environments.
DNA is responsible for transcribing information to RNA which translates information to form proteins which are further responsible for synthesising polysaccharides and lipids. The macromolecules RNA, proteins, lipids and polysaccharides are fundamental to life (Reece, 2012) So essentially without DNA this passage of information cannot occur and life cannot continue. (htt) The cycle allowing the channel of information from DNA to protein is that of protein translation.
DNA consists of a biochemical mechanism that enables the storage, translation and transmission of information (Jobling., 1996)...
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...two identical sister chromatids joined by a centromere. the mitotic spindle, consisting of microtubules and centrosomes then begins to form as centrosomes move to opposite sides of the cell. During Pro-metaphase the microtubules enter the nuclear space and begin to join to kinetechore proteins that are attached to each chromosome. Metaphase occurs when chromosomes move to the metaphase plate that is equidistant from the two centrosomes. Anaphase is the process where sister chromatids separate and move to opposite ends of the cell. At the same time the cell begins to elongate as the process of cytokinesis begins. Once the cell has two complete sets of chromosomes at either end Telophase begins. Nuclei form around the sets of chromosomes as chromosomes become less condensed and spindle fibres disappear. Cytokinesis, the division of the cytoplasm then occurs.
Meiosis
During interphase, the cells in both animals and bacteria carry out their division general functions according to the type of their cells. Unlike in plants, a preprophase group of cytoskeletal proteins emerge at a future location of the cell plate. At prophase stage, duplicated chromosomes compress in a way that can be seen with the help of a microscope. On the other hand, the mitotic spindle is formed at one side of nucleus, whereas in plants, spindle is formed around the nucleus. During prometaphase in animals and bacteria, the nuclear membrane disappears, the chromosomes attach themselves to mictotubules and start to move. In plants, however, the preprophase group dissolves while at metaphase stage, the chromosomes get aligned at the core of the cell. At anaphase, there are fewer differences between animals and plants. The chromosomes shift apart towards the both par...
DNA (Deoxyribonucleic acid) is a molecule found in in the nucleus of all cells in the body which carries our genetic information. DNA is found in the form of chromosomes, with a total of 23 pairs in the human body1. DNA holds the genetic coding for all our characteristics, i.e. our eye colour, body shape, and how we interact with others on a daily basis.
DNA is the blueprint of life from its creation to its development and until its death. The discovery of the structure of DNA not only revolutionized science and medicine, but it also affected many other facets of existence: evolutionary, industrial, legal, and criminal justice. Its incarnation has benefitted American families and industries and spurred scientific innovation throughout the country. Aptly stated by Francis Crick, “your joys and your sorrows, your memories and your ambitions, your sense of identity and freewill, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules. As Lewis Carroll’s Alice might have phrased it: ‘you’re nothing but a pack of neurons.’ [Watson and my] discovery illustrates how that is possible.”
Since DNA has the instructions for making the proteins, but it has to be highly protected, it doesn’t leave the nucleus where it is mostly found (Hall, 6). DNA’s function is to be a long-term storage and transmission of the genetic information (DNA vs RNA, 2014). Copies of certain instructions needed for proteins can be made in the form of RNA. It’s not an exact copy of what is found in DNA, but RNA can travel out of the nucleus with the instructions. RNA make...
In April of 1953, James Watson and Francis Crick published a game changing paper. It would blow the mind of the scientific community and reshape the entire landscape of science. DNA, fully knows as Deoxyribonucleic Acid is the molecule that all genes are made of. Though it is a relatively new term with regard to the age of science, the story of DNA and the path to its discovery covers a much broader timeframe and had many more contributors than James Watson and Francis Crick. After reading the paper the audience should have a better understanding of what DNA is, the most important experiments that contributed to its ultimate discovery and the names and contributions of the lesser-known scientists that helped Watson and Crick turn their idea
In telophase, these separate chromatids uncoil to become chromosomes. This division produces two identical cells.
The process of mitosis can take place in either a haploid (23 chromosomes) or a diploid (46 chromosomes) cell. Before a cell can be ready for a mitotic division it must primarily undergo its interphase stage. Following the interphase stage several other stages come into play. These stages are prophase, prometaphase, metaphase, anaphase, and telophase. During each specific stage certain sequences of events take place that assist to the completion of the division.
Chemistry dictates the structure of DNA. DNA is a polymer of monomers called nucleic acids. These are made of a nitrogenous base, a phosphate group and a sugar. It is the negative charge on the phosphate group that makes DNA an acid. There are 4 different bases: adenine, thymine, guanine and cytosine. In groups of three, these four bases can code for any protein coded for in an organism’s genome. Two strands of nucleic acids stack on top of each other in a double helix. The backbone of the nucleic acids consists of the interaction between phosphate groups and the hydroxide groups of nucleic acids. These are held together by covalent bonds called phosphodiester bonds. The helix itself is held together by hydrogen bonds. Although h...
All living things contain DNA. The molecule deoxyribonucleic acid or DNA is what contains an organism’s genetic information. The genetic information contained in DNA is what an organism requires to not only develop and reproduce but also survive. A DNA molecule is built up of nucleotides. Nucleotides are composed of several different things and what the nucleotides are composed of determines the name of it. Another job of DNA is to pass the genetic information through the process of protein synthesis. The DNA can show birth defects in the fetus using different testing. The knowledge of the birth defects of the fetus can be both positive and negative. DNA is a simple yet complex molecule that is used by all living things and makes us the way
1. DNA is a nucleic acid that carries the genetic information in the cell and is capable of self-replication and synthesis of RNA. DNA consists of two long chains of nucleotides twisted into a double helix and joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine. The sequence of nucleotides determines individual hereditary characteristics.
"The discovery of the structure by Crick and Watson, with all its biological implications, has been one of the major scientific events of this century." (Bragg, The Double Helix, p1) In the story of The Double Helix, James Watson tells of the road that led to the discovery of life's basic building block-DNA. This autobiography gives insight into science and the workings within a professional research laboratory that few members of society will ever be able to experience. It also gives the reader an idea of the reality of life for one scientist and how he struggled with the problem of DNA. However, the author's style is marked by his lack of objectivity and inclusion of many biased opinions and personal prejudices.
Simply put, DNA contains the instructions needed for an organism to develop, survive, and reproduce. The discovery and use of DNA has seen many changes and made great progress over many years. James Watson was a pioneer molecular biologist who is credited, along with Francis Crick and Maurice Wilkins, with discovering the double helix structure of the DNA molecule. The three won the Nobel Prize in Medicine in 1962 for their work (Bagley, 2013). Scientists use the term “double helix” to describe DNA’s winding, two-stranded chemical structure.
Francis Crick, co-discoverer of DNA, has said that “the origin of life appears to be almost a miracle, so many are the conditions which would have to be satisfied to get it going” (Horgan 27).2 Noted evolutionary astronomer Frederick Hoyle has described the chances of life having evolved from nonlife to be about as likely as the chances that “a tornado sweeping through a junkyard might assemble a Boeing 747 from the materials therein” (Johnson 106). Why do respected scientists doubt what textbooks teach as fact? It would appear that these scientists know something that current theories describing the origin of life fail to explain. While current theories describe scenarios in which genetic material such as RNA becomes entrapped in a protective cell membrane as a likely recipe for the formation of life, they generally do not focus on the difficulties of forming and concentrating all of these components in the first place.3 To clarify, current theories suffer from what I call the “cookbook mentality.
There are certain things that must happen first before the cell can actually split. There is a six step process required during Mitosis. The first five steps of mitosis are called prophase, prometaphase, metaphase, anaphase, and telophase. This is where all the training and preparation is done for cell division. The sixth step is Cytokinesis, and that is when the cell literally splits into two. Like I said, there are certain things in order to happen before it can enter the M phase. first, it must meet the requirements of the certain size and environment. Since in the S phase the cell duplicated it’s amount of chromosomes it be represented as 2N, where N equals the number of chromosomes in the cell. Cells about to enter M phase, which have passed through S phase and replicated their DNA, have 4N chromosomes. Because of this they are now allowed to enter within the M phase to prophase. Here is where the cell thickens up its chromosomes and begin to sprout microtubules from clone centrosomes. Microtubules tub-like are protein filaments and where the chromosomes migrate but are still within the nuclear envelope in the nucleus. There are centromeres, that are inside the chromosomes and during the later process of this phase, specialized microtubules called kinetochores, assemble on the centromere then later attach to these sites. They act like magnets and go