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AS and A Level: Genetics, Evolution & Biodiversity
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three domains are archaea, bacteria and eukaryota Niches: * The niche of a species is the way that the species exploits its environment * If two different species are present in the same niche at the same time, there will be competition and one will out compete the other so that the better adapted will survive Types of adaptation: * Anatomical: a physical/structural adaptation, it may be external or internal e.g. kidneys of some desert mammals are modified to reduce water loss by producing very concentrated urine * Behavioural: a change in the behaviour of an organism to increase its survival chances e.g.
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The purpose of this experiment is to identify plant pigments by separation, using thin layer chromatography.
Biomass is a biological material derived from living organisms. In the context of biomass for energy, this is often used to mean plant based material, but biomass can equally apply to both animal and vegetable derived material. Biomass is the dry mass of a living organism. It is simply the actual mass minus the total amount of water. It is calculated by baking an organism in an oven and evaporating off the water present. Biomass can be burned directly, or converted into a gas or oil, to generate electricity and heat.
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It is also used in very young newborn babies in order to carry out treatment as soon as possible if a baby has cystic fibrosis. Identification of carriers is usually carried out if one member of a family is born with cystic fibrosis as this will help other members of a family to identify whether or not they are carriers of the disease and thus allowing them to make informed decisions in their future. An identification of carriers test is conducted by taking a small sample of blood or some cells from the inside of the mouth can be used to carry out a simple test to identify the mutations in the CFTR alleles for cystic fibrosis.
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This causes the artery to become narrower which result in raised blood pressure. Figure 1: Google Images A blood clot may also form which can block the artery as a whole which reduces the flow of oxygenated blood back to the heart which can result in a heart attack. A blood clot can also cause stroke, pulmonary embolism and atrial fibrillation. Statistics show ?69% of people who have a first heart attack, 77% of people who have a first stroke and 74% of people with chronic heart failure have high blood pressure?.
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M2. Discuss the impact on individuals and society of genotypes resulting in developmental delay or impairment of normal body functioning
Translocation DS- where some of or the entire third 21st chromosome is trans-located to another chromosome, usually the chromosome 14. This only occurs in about 3-5% of the Downs Syndrome population. Down?s syndrome is a life- long condition which develops whilst the baby is in the womb; affecting the individual?s normal physical development and causes moderate to severe learning difficulties. This is due to the fact that Downs syndrome causes the brain cells to deteriorate faster than a normal persons.
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Some of the greatest breakthroughs in biotechnology include cloning, stem cell technology, in-vitro fertilization and genetically modified foods, which are also known as GMO?s. Genetically Modified Foods: In the early 1990?s, genetically modified foods were introduced on the market. In order to obtain more beneficial sugars or vitamins in specific foods and to decrease harmful substances in food, scientists created these genetically modified foods. Soybeans, canola, corn, and cottonseed oil were the most usual foods to be genetically altered (7).
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The Huntingtin or HTT gene is on the 4th chromosome of the Human genome and Huntington's disease is caused when the coding for the HTT gene is altered (a mutation). The mutation that causes Huntington's occurs where a region in the DNA strand that codes for HTT is repeated. This region involves the CAG code. This segment of the HTT gene is normally repeated 10 to 35 times and is known as the CAG trinucleotide repeat. People who have more than 40 repeats will almost always develop Huntington's disease.
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In this essay the researcher will discuss the impact of Multiple Sclerosis and how it affects the immune system
Multiple Sclerosis can affect both males and females and usually starts between the ages of 20-50 years old. Multiple Sclerosis is believed to be the cause of damage to the myelin sheath which protects each nerve fiber disrupting the transfer of impulses from the brain to the body. There are four types of MS which are, Relapsing-Remitting MS which is clearly defined attacks followed by complete or partial recovery, Secondary-progressive MS which occurs 10-20 years
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Also it makes their feathers lose insulation causing them to catch hypothermia which can cause death if not treated. Two examples of oil spills that affected the population of the Spheniscus demersus are: June 1994, an oil spill off South Africa?s Cape peninsula affected 40,000 birds (5). June 2000, an oil spill in South Africa affected 40% of the population in the wild (1). From both of these oil spills, 30,000 of the birds that were oiled died (6). Solving the Problem As the population of the Spheniscus demersus is continuing to decrease, certain actions have had to be made in order to conserve the life of these penguins.
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The Emergence of Life on Prebiotic Earth: The Origin of Life, Self Replicating Metabolic Pathways & The RNA World
The Miller-Urey prebiotic synthesis model dominated the field until the 1980?s. However, it eventually fell out of favour, after new research showed it was unlikely that the Earths early atmosphere contained the high concentrations of reducing gases required by Millers model. Even while the prebiotic soup theory was at the height of its popularity it faced an insurmountable problem. For a biological cell to arise from even the most favourable free solution of organic compounds seems unlikely, given that all life is DNA (deoxyribonucleic acid)
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They are more common in women and they often become less severe and less frequent with age. Migraine is the most common neurological condition in the developed world. It is more prevalent than diabetes, epilepsy and asthma combined ? eight million people in the UK have migraine1. Phases of a migraine Migraine attacks follow a pattern consisting of the 5 phases described below. Phases 3 and 4 are prerequisites of a diagnosis of classical migraine. 1. Prodrome 1. Subtle symptoms; may not be noticed 2. Craving to eat sweet foods 3. Mood variations 4. Tiredness 5. Mild photophobia (is a symptom of abnormal intolerance to visual perception of light)
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A study into the effectiveness of Hydroxycarbamide (Hydroxyurea) in treating the complications caused by Sickle Cell Anaemia and side effects caused by taking the drug:
This reduces the threat of Crisies? to an affected person. Red blood cells are the body?s principal means of transporting oxygen around the body. Sickle cell anaemia is a genetic blood disorder where red blood cells develop abnormally. These cells are rich in iron containing haemoglobin which bind to oxygen and are responsible for the blood's red colour. In humans, red blood cells are flexible biconcave disks. Sickle cell anaemia however, contains an abnormal type of haemoglobin called ?haemoglobin S?.
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These beneficial mutations are passed on to the next generation. Over time, beneficial mutations accumulate and the result is an entirely different organism (not just a variation of the original, but an entirely different creature). (Darwins theory of evolution.com) Modern man has evolved slowly over the course of millions of years, with many factors playing a part. Jenine Smith Australopithecus Afarensis. 4 -2.7 million years BCE. East Africa. A.Afarensis is the longest lived and most known species of early human and had both human and ape-like characteristics - a small brain, long strong arms for climbing and small canine teeth for feeding on a diet of plants, seeds, insects and fruits and a round body to accommodate the amount of intestine needed to digest tough plant foods.
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Human presence on the islands has also brought pollution and habitat destruction. The growing traffic of people and goods has increased the possibility of species introduction - a major threat to the fragile ecosystem. Introduced species, including rats and domesticated animals such as goats and pigs, compete with native species for food and prey on the eggs and young of reptiles and birds. A tanker smashed into the rocky coastline when it mistook a buoy for a light house. The ship, called ?The Jessica?, dumped thousands of gallons of oil into the bay of San Cristobal Galapagos Island At the
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So factors like velocity of water and amount of plant life in the water can effect how much dissolved oxygen is inside of it.  Oxygenation levels must be over a certain concentration for aquatic life to survive, it must not reach too high, as that can be dangerous for the organisms living in the water. A scientific journal I have found during research states that: ?Safe concentrations of dissolved oxygen for survival and adult emergence of larvae of nine species of aquatic insects, including mayflies, stoneflies and caddis flies ranged from 0.6 mg/litre for the midge Tanytarsus dissimilis to slightly less than saturation for the emergence of Ephemera simulans (18.5 C).
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The process of genetic modification is not too dissimilar to gene therapy: first, the desired gene must be isolated. This can be done by using restrictive endonuclease, an enzyme that ?cuts? DNA at specific points or if the DNA sequence is known, the gene can be artificially synthesised using free nucleotides without the use of a DNA template however this can often lead to defects, especially in longer chains.  The desired gene is then put through a polymerase chain reaction (PCR), which copies and multiplies the gene by replicating and transcribing (polymerising) the gene repeatedly, making it easier to work with .
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As recent as the 1950s DNA had still not been identified, but the race to do so was in full swing. Today it is credited to James Watson and Francis Crick while working in England. This led to Herbert Boyer?s breakthrough synthesis of human insulin from genetically modified E. Coli bacteria In the late 1970s. This was a momentous step in the treatment of diabetes as before the only treatment was using donor or animal insulin, which was not as effective and could lead to other complications.
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Scientist Ian Wilmut produced Dolly the sheep using nuclear transfer method after his ten years work. Cloning technique can actually improve and benefit a lot of condition globally. Cloning could be used to increase population of endangered animals species which could lead to a better environment and save the nature habitat key chain of wildlife. It?s also beneficial in medical purpose, including create healthy lungs to cancer patients and produce rare types of blood for hospital usage. Because of small group amount of donors and the scarcity of wildlife habitat, the cloning and bioengineering technique could definitely benefit and improve the society.
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With the aid of specific examples, describe the concept of a hierarchy of biological organization. What is meant by the phrase the whole is greater than the sum of its parts?
The hierarchy of biological organization is a group of different systems that sustain life through emergent properties. The first four levels of this organized group are the biosphere, ecosystem, community, and population. The biosphere contains all the living and nonliving matter here on earth. The nonliving matters, such as sunlight, wind, and bodies of water and land have a direct effect on the living matter contained in the biosphere. The second level is the ecosystem which at various locations, contain all living organisms and nonliving matter in one place.
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It is not available to all women, it is only for those who 1. Are over 35 2. Has a family history of genetic/chromosomal abnormalities 3. Failed attempts of IVF 4. Had three or more miscarriages The reason for these strict guidelines is because that when you are older, the likelihood of issues to do with birth or genetics is higher. The reason for this is because as you get older, the cells are older too which means that the cells are likely to be mutated or mutating which can lead to problems in having birth.
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(de Dios Vial Correa, year unknown, internet) Furthermore, the issue of whether human clones are subject to all human rights are questioned, it is ambiguous regarding this issue. Lastly, the issue of ?expectation? is common in cloned children, they are likely to be expected to excel in a certain area depending on the cloned parent whom genes are extracted. In other words, such expectations will exert a significant amount of psychological pressure on human clones, especially when growing up. Moreover, the future path of human clones may be decided even before their birth, thus leaving no options of self-independence.
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of alleles by purely random processes, as allele frequency fluctuates between generations due to sampling effects. The smaller the population, then the higher the chance that major changes in gene frequency can occur. If an individual possesses a new beneficial mutation, this mutation can still be lost when it occurs at such a low frequency. A chance event may kill the individual losing the mutation forever. These kinds of events have shaped evolution, showing there is chance involved even after the random mutations have occurred. As random genetic drift and evolution are the two main influences on the ?change in allele frequency through time?, then it is important to establish how much each part has to play within evolution in order to ascertain the effect of chance on evolution.
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Steroids can be taken to help reduce the swelling in the lungs. DNase can also be taken which thins out the mucus found in the lungs making it easier to be coughed up. A type of treatment used to help the digestive system is a supplement of vitamins A, D, E and K these are taken along with a well balanced diet which is low in fat and high in calories, proteins and pancreatic enzymes. A new therapy that has been introduced is gene therapy.
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