Lab 1: Ethical Issue in the Movie Gattaca. The epicentre of ethical issues in the movie Gattaca is the manner in which an individual ought to be judged. Should it be by the genetic composition one is born with or by the character traits, personality attributes and ambitions chosen by an individual? Vincent is born with genetic weaknesses that could result in ailments in the future. His genetic composition denies him access to his dream job despite the fact that he achieves the required grades in school and is a strong and athletic young man. As a result, Vincent designs a plan to cheat his way into the program by using Jerome Morrow’s identity.
Jerome is a paralyzed individual but with superb genetic composition and is not interested in joining the Gattaca facility. He is not opposed to the idea and thus Vincent is sure he will not raise any issues of concern. Had the recruitment process included a one-on-one interview on the knowledge of astronomy, physical skill and enthusiasm for space exploration, Vincent could stand a chance but now he was locked out rather unfairly due to the emphasis on genetics. It is probably these that led Vincent to break the law and assume someone else’s identity so as to get into the program. Although he broke the law, the moral standing of his actions in not shaken since, in the process, no one was hurt or killed. There was no loss of property or infringement of another person’s rights. On the contrary, his actions benefited not only himself but others too. Vincent pursues his freedoms and rights despite the prejudice that stood against him and is eventually granted the same treatment as the genetically superior individuals. This proves the comparative justice test is passed, genetics alone should not be used to judge an individual.
Lab 2: Phases in Mitosis. Mitosis is the process through which an organism grows or repairs damaged tissue. Mitosis occurs only in eukaryotic cells, the process varies in different groups. The process of mitosis is fast and highly complex. The sequence of events is divided into stages that are measured about the completion of one set of activities and the commencement of the next stage. Apparently, Mitosis results in the transfer of the parent cell's genome into two daughter cells. These two cells do not differ in any way. There are four phases in the mitosis process. The first phase of the process is called the prophase. In plant cells only, prophase is preceded by a pre-prophase stage. The nucleus migrates into the centre of the cell in highly vacuolated plant cells before mitosis can begin. The chromosomes that were replicated during the interphase become more visible at this stage. Moreover, the centrioles divide, the nucleolus disappears, and the nuclear membrane also begins to disappear (Cregan, pg 72). This is of importance because the cell does not need to divide the nucleolus right away. It will be regenerated when the nucleus divides completely. Some fibres cross the cell to form the mitotic spindle. Once this is complete, the second phase begins. In the case of a pre-metaphase, the nuclear membrane dissolves, marking the beginning of pre-metaphase. Proteins get attached to the centromeres forming the kinetochores. Microtubules attach at the kinetochores, and eventually chromosomes start moving. The second phase of mitosis is known as the metaphase stage. During this phasethe, two centrosomes start pulling the chromosomes through their joined centromeres towards the two ends of the cell. This results in longitudinal tension on the chromosomes from the two poles of the cell. The fibres of the spindle get aligned along the metaphase plate that is located in the middle of the cell nucleus. This ensures that, in the next phase, when the chromosomes separate, each new nucleus will receive one copy of each chromosome. The second last phase of mitosis in called the anaphase stage. During this phase the centromeres attaching the homologous chromatids break, chromatids migrate towards the poles of the cell. Motion is as the results of combined kinetochore movement along the spindle microtubules and the physical interaction of polar the microtubules. In the last stage, the telophase stage, chromatids cluster at the poles, allowing the chromosomes to disperse and making them invisible. The spindle fibres get dispersed, and the partitioning of the cell also begins during this stage. The nuclear membrane is formed in each of the cells, resulting in a split into two cells each with an equal number of chromosomes.
Lab 3: DifferencesBetween Mitosis and Meiosis. There are three major differences in the events of mitosis and meiosis. In mitosis, there is only one division resulting in two cells while, in meiosis, there are two divisions resulting in four cells. The prophase stage in meiosis involves pairing of like chromosomes while, in mitosis, they do not pair. Pairing occurs in prophase II (Cregan, pg 98). In mitosis, the chromatids separate whereas, in meiosis, they stay together. Separation takes place in anaphase II. At the end of telophase in mitosis two identical cells are formed while in meiosis the cells are formed at the end of telophase II
Lab 4: Non-Mendelian Characteristics in Human Blood. Human blood exhibits two non-mendelian characteristics. These are incomplete dominance and co-dominance (Kusick, pg 137).
Incomplete dominance is usually the case when a heterozygote has intermediate phenotype. An example is where blending occurs in the phenotype; there is incomplete dominance that results in an intermediate expression of a trait in the heterozygous individuals. For instance, in some flowers, red or white flowers are homozygous while pink ones are heterozygous. The pink flowers are as a result of the inability of the plant to produce red pigment in a process known as coding. The pitch of male voices is an absolute example of this situation in humans. The lowest and highest pitches are found in men who are homozygous for the pitch trait.
Co-dominance is observed when the heterozygote exhibits both allele’s traits. For some traits, two alleles can be co-dominant. This means that the two traits are well expressed in heterozygous individuals. A perfect example of this is people with AB blood type for the ABO blood system. These individuals display the characteristics of both blood group A and B. Moreover, their phenotype is not intermediate between the two but is instead an exhibition of both in equal measure. The ABO blood type system also provides the example of traits that are controlled by more than just a single pair of alleles, traits that are due to a multiple-allele series.
Lab 5: DNA Transcription. Transcription is usually the first scientific step in gene expression. It is a process that involves transcribing genetic information from DNA which consists of the nucleotide bases adenine (A), guanine (G), cytosine (C), and thymine (T)to RNA. These bases are paired together to give DNA its double helical shape. The sequence of the nucleotide base provides the genetic code which is like a set of instructions for the manufacture of proteins. The process of DNA transcription takes place in three main stages. In the first stage RNA polymerase is bound to the DNA, which then transcribes the DNA. Specific nucleotide sequences usually guide the RNA polymerase on where to start and where to complete the process. RNA polymerase is attached to the DNA’s promoter region. The next step is Elongation. During this process, certain proteins called transcription factors unwind the DNA strand. This allows the RNA polymerase to work on a single strand of DNA converting it to a single stranded RNA polymer known as the messenger RNA (mRNA).The antisense strand is the name given to the strand that acted as a template while the one that was not transcribed is known as the sense stand. RNA is also composed of nucleotide bases but has uracil in place of the thymine found in DNA. During the transcription, guanine pairs with cytosine and adenine pairs with uracil. The final stage is termination. RNA polymerase moves along the DNA eventually reaching a terminator sequence. RNA polymerase releases the mRNA and detaches itself from the DNA. Proteins are constructed in the cytoplasm of the cell and mRNA must cross the nuclear membrane to reach the cytoplasm. In the cytoplasm, ribosomes and the transfer RNA translate mRNA into a protein. This process is called translation.
Lab 6: DNA Translation. In molecular science, translation is the process in which cellular ribosomes synthesis proteins and is part of the gene expression process. The process takes place in four stages; they are initiation, elongation, translocation and termination (Farber, pg 93). In the translation phase, the mRNA initially produced through transcription is decoded to make an amino acid chain that later folds to create an active protein. In bacteria, the translation process occurs inside the cytoplasm. This is because it is where the large and small subunits of the ribosome are located, and are bound to the mRNA. In eukaryotes whoever, translation occurs across the endoplasmic reticulum membrane. A process referred to as vectorial synthesis. The ribosome help the decoding process by inducing the binding of tRNA’s with complementary anticodon sequences to that of the mRNA.
Lab 7: Does DNA Presence Imply Guilt? DNA evidence is one of the most commonly known kinds of scientific evidence. It is gathered through the forensic combing of a crime scene to obtain any substances that can give up DNA when processed in a lab. For example in rape cases, the victims are often advised not to take a shower before a medical examination has been conducted. These provide for the collection of DNA samples from semen or other bodily fluids so as to ascertain that a crime took place. DNA evidence thus uses this scientific evidence in order to provide conclusions for proving a particular case in the trial.
The presence of this evidence alone cannot be used as a basis for conviction since all it can prove is that the person indeed had sex with the alleged victim but it does not tell whether it was forced, or it had been mutually agreed between the two parties. This means that it cannot stand on its own as evidence as it is ultimately considered to be circumstantial evidence. This means that it does not definitively prove guilt of the suspected party.
Lab 8: Evolution in Bacteria. Evolution can be defined as the changes that occur in a species over a period. Evolution is usually extremely slow and cannot be observed in the life span of the average human. However, some species have the capability to reproduce very quickly thus making it possible to see the evolutionary changes taking place. One such organism is bacteria which most commonly reproduce by fission, or splitting in two. Some take longer but most even undergo fission in mere minutes. This allows the species to produce multiple generations within a single day. Since the accidental discovery of penicillin by Alexander Fleming in 1928, antibiotics have been used on a worldwide scale to eliminate bacterial infections. Antibiotics work in a similar manner as the naturally occurring antibodies found within the human body.
Some bacteria may possess a trait that enables them to survive an attack by an antibiotic, meaning that they have naturally occurring resistance to the drug. This is known as the favourable trait required for survival and as the other bacteria are eliminated by the antibiotic, those with the strain survive. Eventually, only those that are resistant to the drug remain and since they reproduce very quickly the numbers just keep on increasing leading to a large population of drug resistant bacteria. This process explains how bacteria can be found surviving within the inhibition zone of an antibiotic.
Lab 9: Primitive versus Complex Plants. Primitive plants are plants that existed a long time ago and most have been phased out by the effects of climate change and the need for them to evolve in order to survive. Very few of these primitive plants exist today, but one exists in abundance and is the algae. The plants that managed to evolve became very complex with their parts performing different functions. The major difference between complex plants and primitive is that complex plants have evolved to form various parts with different functions. Each of these parts has different responsibilities with some of them taking up nutrients and minerals, while others are responsible for respiration. This has resulted in complex plants having connective tissues while the primitive plants still lack this. The connective tissue is used to transfer water that carries everything the plant needs to different parts. Most primitive cells have each cell absorb water from a source on its own. The reproduction system of complex plants is more developed unlike that of primitive plants that is formed when a cell splits into two. Thirdly, primitive plants can be single-celled while complex plants are all multicellular organisms.
References
Elizabeth Cregan 2007 All about Mitosis and Meiosis Teacher Created Materials
Emmanuel Farber 1972 The Pathology of Transcription and Translation M. Dekker
IlonaMiko, Ph.D. Mitosis, meiosis and inheritance.Scitable a Learning Space for Science 2008. Web. 06 March 2014 <www.nature.com/scitable/topicpage/mitosis-meiosis-and-inheritance-476>
G. Stolyarov II. An Analysis of Ethical Issues in the film “Gattaca”. Yahoo Voices 31 May 2007 <www.voices.yahoo.com/ an-analysis-of-ethical-issues-in-the-film-gattaca-369301.html>
Victor A. McKusick 1998 Mendelian Inheritance in Man John Hapkins University Press
