"Anorexia Nervosa cannot be satisfactorily accounted for by any single model of abnormality" - discuss

"Anorexia Nervosa cannot be satisfactorily accounted for by any single model of abnormality" Anorexia is a condition disputed by psychologists in attempts to find a cause for the problem. Anorexia is when an individual chooses to emaciate themselves in order to be thin. There are two main types of reasoning behind such behaviour. The biological and psychological explanation. Of course, there are many forms of branched out explanations within these, and the two of which that I shall be exploring are the genetic justification (in terms of biological) and the behaviourist approach, for the psychological relation. Biological psychologists believe that human behaviour and what makes us do what we do, is all down to genes. With the new advance in recent science, genes are becoming a more popular reasoning to many psychological issues. Anorexia nervosa for one. The genetic approach proclaims that the cause for anorexia is to do with genes: i.e. the genetic and inherited factors we have within our relations. The idea is that should one family member suffer from an eating disorder, then there is a higher chance that another family member (preferably those who share the same, or like genes) would contract an eating, or another obsessive-compulsive disorder. Holland et al, a group of psychologists, lead a study on the genetic link of anorexia nervosa in 1984. They perused a sample of

  • Word count: 1018
  • Level: AS and A Level
  • Subject: Science
Access this essay

Parkinsons Disease

Parkinson's Disease (PD) The problem: At the moment there is no cure for PD and treatments still have a long way to go before PD is no longer a major issue. But the real problem is which treatments to use and which path shows the most potential to a full time cure? Introduction: PD normally affects people over the age of 50. It becomes more common with increasing age. 'About 5 in 1,000 people in their 60s and about 40 in 1,000 people in their 80s have PD'1. It affects both men and women but is a little more common in men. PD is not usually inherited, and can affect anyone. However, genetic factors may be important in the small number of people who develop the disease before the age of 50. PD therefore affects a lot of people in the UK and I have chosen this topic so I have a greater understanding of what they go through and how we can help those affected. Background: Biology of Parkinson's disease? Parkinson's disease is a chronic disorder of part of the brain called the substantia nigra. It mainly affects the way the brain co-ordinates the movements of the muscles in various parts of the body. This area of the brain sends messages down nerves in the spinal cord to help control the muscles of the body. Messages are passed between brain cells, nerves and muscles by chemicals called neurotransmitters. Dopamine is the main neurotransmitter that is made by the brain

  • Word count: 3857
  • Level: AS and A Level
  • Subject: Science
Access this essay

Should everyone be to taking statins to reduce the risk of cardiovascular disease

Should everyone be to taking statins to reduce the risk of cardiovascular disease? Cardiovascular disease is one of the biggest killers of the modern world. Approximately 70,000 people die from cardiovascular disease or its complications every year in the UK alonei. Worldwide it claims over 17.1 million lives a yearii. Although CVD is a multi-factorial disease with many preventable and non-preventable causes, studies have shown that there is a high correlation between high LDL levels and the incidence of CVDiii. Statins are a group of drugs designed by the pharmatsuitical industry to reduce levels of LDL in one's blood. Low density lipoproteins are protein molecules made up of both triglycerides and cholesterol. Cholesterol is a sterol which means in it insoluble in water. In order for it to pass through the blood stream and diffuse through cell membranes it needs to be attached to a soluble chain molecule such as a triglyceride. Most cardio-vascular events start with the formation of an atheroma, which is an acculmation of fatty deposits in the artery walls between the inside of the artery (lumen) and the elastic muscle layer. An atheroma can lead to the narrow of the lumen in a process called stenosis which increases the patient's blood pressure. The blood constantly hitting the atheroma as it juts out into the lumen can cause it to harden. Often this leads to a

  • Word count: 2638
  • Level: AS and A Level
  • Subject: Science
Access this essay

The aim of this experiment is to research on the effect caffeine has on Daphnia heart rate.

THE EFFECTS OF CAFFEINE CONCENTRATION ON DAPHNIA HEART RATE AIM The aim of this experiment is to research on the effect caffeine has on Daphnia heart rate. To enable this, a certain percentage of caffeine solution was tested on Daphnia (water fleas) as it will be a lot easier to monitor their heart rate due to their translucent body. This practical will help develop data representation and improve key practical skills. INTRODUCTION Caffeine is an odourless, slightly bitter alkaloid found in coffee, kola nuts and small amounts of cocoa. In humans, Caffeine acts as a stimulant on the central nervous system preventing drowsiness temporarily in order to keep the brain 'alert'. Caffeine is one of the world's most popularly used drugs and acts a mild diuretic in humans and animals. It will be unethical to carry out this experiment on humans as they have a high level tolerance to caffeine as it was proven in a recent experiment that higher concentrations of caffeine solution causes the heart to beat abnormal fast so an alternative source. Daphnia will be used to carry out this investigation as their resting heart rate is very high and this will air to provide rapid results. .1. Diagram of a typical Daphnia Daphnia are small water crustaceans which share a slight resemblance to water fleas and are mostly found in lakes and ponds. Food sources and beverages containing caffeine

  • Word count: 1830
  • Level: AS and A Level
  • Subject: Science
Access this essay

Global climate change. Greenhouses gasses that warm the earths surface are water vapor, carbon dioxide, and methane. When light from the sun reaches earth, it is reflected back into the earths atmosphere as infrared radiation.

Cesar Martinez Dr. Coburn Bio 1 T/TH October 26, 2009 Global Climate Change According to an article by the British Broadcast Corporation (BBC), the United States emits more greenhouses gases per person then any country in the world. Although greenhouse gases occur naturally in the earth's atmosphere, humans have rapidly increased the amount of carbon dioxide (CO2) in it. All the excess carbon dioxide has caused a gradual increase of the earth's temperature, which we call global warming. Scientists believe global warming is most likely caused by human. Although many people think global warming is not real, I believe global warming is the most important issue facing the world. The burning of fossil fuels and deforestation are the main causes for global warming. The effects of these could have a devastating effect on earth. Effects like the spread of disease, drought, extreme weather patterns, and even the extinction of animals. There are many changes we can make to combat global warming like using alternative fuel sources like nuclear, solar, and hydrogen. Greenhouses gasses that warm the earth's surface are water vapor, carbon dioxide, and methane. When light from the sun reaches earth, it is reflected back into the earth's atmosphere as infrared radiation. Once infrared radiation is reflected back into the atmosphere, greenhouse gases absorb the radiation and reflect it

  • Word count: 1505
  • Level: AS and A Level
  • Subject: Science
Access this essay

Effect of Tourism on Sea Turtles

Threats to Marine Turtle Survival The Problems, Risks to Turtles and Examples Today the seven species of marine turtle that swim our oceans are all included on the World Conservation Union's (IUCN) Red List of Endangered Species [1]. Before human intervention, it was thought that only one in one thousand turtle eggs actually survived to become adults. With human as well as natural threats, it is estimated to be up to one in ten thousand [2]. Figure one clearly illustrates how the number of leatherback turtles nesting has fallen in Playa Grande and Ventanas, popular tourist destinations. There has been 95% decrease in the number of female leatherbacks between 1988 and 2002 and there are multiple reasons that have contributed to such a steep fall. This report will concentrate on tourism related threats. Unfortunately human threats now add to threats posed by nature and if it was not difficult enough to survive before, turtles now have to contend with problems we create. Marine turtles breathe with lungs. This forces them to surface in order to inhale air. The heart (see figure 2) consists of two atriums but one ventricle and results in an incomplete double circulatory system. This allows them to bear high levels of carbon dioxide in the blood. Blood and muscle tissue can accumulate large quantities of oxygen. These features allow turtles to stay underwater and sleep for up

  • Word count: 2528
  • Level: AS and A Level
  • Subject: Science
Access this essay

what happens to the energy in a boucing ball

In my science general coursework I will be answering the question "What happens to the energy in a bouncing ball?" We all know that when we drop a ball from a height it wont bounce back to the original drop point, but do you know why? This must mean that the amount of energy it started off with is lowered. Where does that energy go? These are all the questions I will be answering by using sources such as textbooks and notes, the marking grid, books in library and the internet. My method for collecting data was very simple. I used two one metre rulers and a tennis ball! By dropping the ball from a range different heights I could put the data into a graph and see if there was a relationship. To make it a fair test I used the same ball on the same surface and whether it was dropped from the top of the ball or the bottom of the ball. It is very easy to make mistakes on such an experiment, it is all done by eye and reaction times so it is not the most precise of methods. To make my data more precise and reliable I carried out the test 4 times and erased any anomalies in my data. Then I averaged the data to get a reasonably accurate graph which showed a visible relationship. I am measuring the mass and the height so I can investigate why there is a loss of energy in the ball as it bounces back. Page 1 Bounce height (m) gravitational potential energy (j) original height

  • Word count: 911
  • Level: AS and A Level
  • Subject: Science
Access this essay

Research the use of recombinant DNA in the production of human insulin and two other named proteins of your choice.

Research the use of recombinant DNA in the production of human insulin and two other named proteins of your choice Recombinant DNA is DNA that has been created artificially. DNA from two or more sources is incorporated into a single recombinant molecule. There are three different methods by which Recombinant DNA is made. They are: Transformation, Phage Introduction, and Non-Bacterial Transformation. In this essay I will be discussing these methods which are used to make insulin, erythropoietin, and factor VIII. Insulin reduces the blood glucose level (BGL) which is raised by the intake and metabolizing of carbohydrates. High levels of glucose in the blood will cause problems so the sugar level must be returned to normal as soon as possible. When the blood sugar level rises, the islets of Langerhans in the pancreas release insulin into the blood. Insulin makes the liver convert glucose to glycogen, which is stored primarily in the liver but also in the muscles - this results in lowering the BGL. When the BGL is low, the pancreas stops producing insulin. Diabetics cannot produce any or enough of their own insulin so they must inject commercially produced insulin. The gene for insulin production that is inserted into bacteria comes from a human chromosome form a pancreatic cell. Erythropoietin is the hormone normally produced by the kidneys of humans, cats and dogs, and other

  • Word count: 1308
  • Level: AS and A Level
  • Subject: Science
Access this essay

Biology Coursework: Does Acupuncture relieve pain?

Does Acupuncture relieve pain? Is this form of unconventional alternative medicine anything more than placebo effects? Acupuncture is an alternative medicine that treats patients by insertion and manipulation of needles in the body. Its practitioners variously claim that it relieves pain, treats infertility, treats disease, prevents disease, promotes general health, or can be used for therapeutic purposes.3 However, explaining the mechanism of acupuncture using conventional science and proving that it relieves pain has proved very challenging for scientists over the decades. This coursework will attempt to explore this topic further and determine whether there is any biological proof that acupuncture reduces pain. Ideas of what constitutes health and healing sometimes differ from concepts used in scientific, evidence based medicine. Acupuncture was developed prior to the science of human anatomy. Disease is believed to be caused, not by infectious agents, but by an imbalance of yin and yang (a metaphysical balance) caused by a "blockage" or "stagnation" of metaphysical energy known as qi (pronounced "chee") which is believed to flow within and without the body. Inserting needles into specific acupuncture points along a meridian unblocks qi and restores the body's healthy balance. 2 Jessica L (fig 1) says, "after my first session, I felt so much more balanced and in control,

  • Word count: 3855
  • Level: AS and A Level
  • Subject: Science
Access this essay

In this paper I will be studying chromosome 11 of the human genome.

Biology ISU Chromosome 11 By: Rachel Williams SBI 4U Teacher: Mr. Pigeon December 5, 2003 In this paper I will be studying chromosome 11 of the human genome. Specifically, I will be researching some of the diseases that occur when there are mutations in the genes on chromosome 11. Five specific diseases will be looked at and studied in detail: the Sickle Cell Anemia gene, the MLL gene which causes Trisomy 11, the H19 gene which causes Beckwith-Weideman Syndrome, the WT1 and PAX6 genes which causes Wilm's Tumor syndrome, and finally, the work being done on the genes of Chromosome 11q22-q24 regarding cervical carcinoma. The following research was all acquired from the NCBI online database. The HBB gene which causes Sickle Cell Anemia, is found on chromosome 11p15.4. This gene causes an inherited blood disorder, mainly effecting people from the African continent (1/500), but also people from the Mediterranean and South Asian countries.(NCBI Online, 24 June 2003) Approximately 8% of the African American population are carriers; often, this gene is associated with malaria occurrence, as carriers are somewhat protected against malaria. (NCBI Online, 24 June 2003) Sickle cell anemia is an autosomal (not sex related) recessive disease caused by a mutation in the hemoglobin beta gene. When a mutation occurs, the HBB gene produces a structurally abnormal hemoglobin (Hb),

  • Word count: 1606
  • Level: AS and A Level
  • Subject: Science
Access this essay