Artificial Cardiac Pacemakers

Research questions : Why is the constant beating of the heart important? What causes the heart to beat abnormally? What are the implications of having an abnormal heart beat? What is an artificial pacemaker and how does it regulate an abnormal heart beat? How are artificial pacemakers implanted? What are the advantages and disadvantages of using an artificial pacemaker? What are some alternatives used instead of artificial pacemakers? The importance of the heart The heart is an essential organ possessed by every living human. It is vital as it pumps blood rich in oxygen (received from the lungs) to every living cell within the body and pumps deoxygenated blood to the lungs (from the body)1. In the opposite diagram of a human heart, the blue sections represent the transport of deoxygenated blood and the red sections represent the transport of oxygenated blood. The heart is necessary in sustaining the lives of every single human being. This is because without oxygen, cells cannot carry out the process of cellular respiration (the release of energy from glucose). This means that the body cells will have insufficient energy to carry out regular functions needed for sustaining life. Every single cell in the human body is affected by the beating of the heart, as enough oxygen has to be supplied for them to function properly. Without the constant beating of the heart,

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Myocardial infarction

Case Study 2006 Myocardial Infarction Sharon Thomas Waitakere Hospital Abstract Of This Case Study Have you ever wanted to know what a Myocardial Infarction is and what its all about. Read on and find out through my eyes, about a patient I was caring for - what happened to him in both his body and mind. The following will show what a Myocardial Infarction ( MI ) is, what happens in the patients body and what care is involved by the medical and nursing teams. All of this to ensure my patient would walk out of hospital and again feel like productive member of society that he most certainly was before his cardiac event. Also within the body of this case study will be evidence based articles to support statements made. Congruent to this, will be reflection on how all that transpired with this man affected me and how my nursing practice has developed because of it. This patients health related journey and the anonymous intimacy that took place, came to a happy conclusion for both nurse and patient. Judith Christiansen's Nursing Partnership Model was published in 1990 and was developed in response to the knowledge gaps in the nursing system in New Zealand ( Taylor, 1995 ). This partnership model is a theoretical framework for nursing practice. It has 3 major concepts - these being nursing partnership, the passage and the context. Anonymous Intimacy is one of 3

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Explain how arteries, veins, and capillaries are adapted for their functions. Describe what happens in coronary heart disease and explain how lifestyle may contribute to the development of this disease.

Explain how arteries, veins, and capillaries are adapted for their functions. Describe what happens in coronary heart disease and explain how lifestyle may contribute to the development of this disease. The human circulatory system is an essential network of tubes designed to transport a continuous flow of blood throughout the body delivering nutrients to and removing waste from every cell. Contemporary society is experiencing an increasing number of people suffering from an often preventable disease that occurs in this circulatory network named coronary heart disease. (Boyle, M., Senior, K. 2002). (www.nhlbi.nih.gov/health/public/heart/other/chdfacts.htm). This essay will explain how the circulatory systems' arteries, capillaries and veins are adapted for their functions, what happens in coronary heart disease, and how some contemporary lifestyles may contribute to the condition. The main organ of the circulatory system is the heart, situated in the chest between the lungs. It is a hollow muscular structure consisting of four main chambers. The lower left and right ventricles have thick muscular walls to pump blood, and the upper left and right atria that have thinner walls and receive blood. This is effectively a double circulatory system as both ventricles pump blood and both atria receive blood simultaneously. The pulmonary system starts in the right

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Investigation into the density of mock blood.

. Assessed practical: A2 Practical. Investigation into the density of mock blood. Aim: to find any difference in blood density in the mock blood samples belonging to: * a healthy male living at sea level (a); * the same male after he has undergone 6 months of regular aerobic exercise (b); * the same male who has spent 3 months undergoing aerobic training at altitude (c). Background knowledge: Blood is composed of watery plasma in which a variety of cells are present. The majority of cells present are red blood cells, or erythrocytes. These are red biconcave discs about 7?m in diameter. They have no nucleus, no mitochondria and no endoplasmic reticulum, this is to maximise the amount of oxygen which can be carried by each blood cell. The red colour is caused by the globular protein haemoglobin. The main function of haemoglobin is to transport oxygen from the lungs to respiring tissue. Oxygen is transported around the body in the red blood cells in combination with haemoglobin. Each haemoglobin molecule is made up of four polypeptides each containing one haem group, each of which can combine with one oxygen molecule. Therefore each haemoglobin molecule can combine with four oxygen molecules. This can be represented by the following equation: Hb + 4O2 HbO8 Haemoglobin oxygen

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Science in the news- should cannabis be legal?

Should the use of cannabis be legalised? Cannabis is a drug derived from the plant cannabis sativa. Cannabis contains more than 400 chemicals, with the main chemical being Tetrahydrocannabinol (THC). Smoking is the most common way of taking Cannabis. Cannabis can be found in hundreds of different substances, but the most common one is marijuana. About 4 percent of the world's population smoke Cannabis annually and 0.6 percent daily (ref 1). I find this fact reliable as it is stated by www.knowcannabis.org.uk, an organisation of Cannabis experts. Cannabis can affect some Social, Economic and Environmental issues, but Cannabis has more of an effect physically within our bodies.Up until 2004 cannabis was a Class B drug but has now been put down to a Class C drug and in 2006, the Home Secretary decided to keep cannabis as a Class C drug. Some people believe that the legalisation of cannabis would lead to an increase in the usage of the drug among young people. They argue that if cannabis was legal, it would be more readily available and therefore more tempting to try. However, others believe that legalisation would cut numbers of cannabis users as the thrill of breaking the law and being rebellious would be taken away. Argument For These advantages are reasonable enough to argue for the legalisation of Cannabis. Cannabis can have a relaxing effect on people, as well as

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Biology notes

AQA GCSE Biology Unit 2 Summary Notes 2.1 Animal and Plant Cells Cells * Cells are the smallest unit of life. * All living things are made of cells. * Most human cells, like most other animal cells, have the following parts: o nucleus o cytoplasm o cell membrane o mitochondria o ribosomes * Plant cells also have: o cell wall o chloroplasts o permanent vacuole What do these structures do? * Nucleus - controls the activities of the cell. * Cytoplasm - where most of the chemical reactions take place. * Cell membrane - controls the passage of substances in and out of the cell. * Mitochondria - where most energy is released in respiration. * Ribosomes - where protein synthesis occurs. * Cell wall - strengthens plant cells. * Chloroplasts - absorb light energy to make food in plant cells. * Permanent vacuole - filled with cell sap in plant cells. Other facts: * The chemical reactions inside cells are controlled by enzymes. Examples: o Enzymes for respiration are in the mitochondria. o Enzymes for photosynthesis are in the chloroplasts. o Enzymes for protein synthesis are on the ribosomes. * Cells may be specialised to carry out a particular function. Examples: Tissues, organs and systems * A tissue is a group of similar cells carrying out a particular function. * An organ is a group of different tissues carrying out a particular function. *

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Analysis of anaemia.

Anaemia Problem Anaemia is a condition resulting from below- normal levels of haemoglobin in the red blood cells. Haemoglobin in the blood is responsible for carrying oxygen to the rest of the body. Anaemia may be due to loss of blood from heavy menstrual periods, from internal bleeding caused by a peptic ulcer, or from haemorrhoids. A healthy person whose diet contains plenty of iron and vitamins can produce large amounts of new blood. However, if your diet is inadequate, even small, persistent losses of blood may cause anaemia. There are several kinds of anemia. Iron-deficiency anaemia can develop in those who do not have enough iron, which is an essential ingredient of haemoglobin. Lack of Vitamin B-12 or folic acid can result in Vitamin B-12 deficient anaemia and folic acid deficient anaemia. Hemolytic anaemia occurs when red blood cells are destroyed more quickly than they can be replaced. The symptoms of anaemia include fatigue, weakness, fainting, breathlessness, and heart palpitations. Aplastic anaemia is a rare disease which affects mostly young men. 2 to 6 people per million worldwide develop this disorder annually but it affects mostly people in the Orient. A variety of associations have been made in the attempt to find a specific cause, but no one cause can be identified. Treatment must be given straight away after diagnosis to avoid fatality. Patients

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Animal Pharming

Animal Pharming My article is on the Animal Pharming. This is a Secondary Genetic modification method of genetic modification. It was developed during the late 1990s, but not yet used commercially used. In the paragraphs to come, I will describe what Animal Pharming is capable of, and my opinion of this form of Genetic Modification. Animal Pharming is the process of using transgenic animals to produce human drugs. Transgenic animals are animals which have been genetically transformed by inserting other animal or human genes into their chromosomes. The inserted gene enables an animal to make a certain proteins in its milk, urine, blood, sperm, or eggs. Also, organs can be grown for transplants. The proteins produced serve many purposes, including treatments for many diseases such as HIV and malaria. These animals can also produce antibodies, which are used in vaccine development. Transgenic animals are very expensive to produce and they have a high value. Also, only a few of the attempts succeed in producing a transgenic animal. The Financial Times predicted that 600 transgenic cows, could supply the worldwide need for pharmaceuticals. Now that computers are being used more in laboratories, scientists have reduced the time needed to identify and collect genes. As gene identifying has become easier, each known gene sequence is recorded and stored. Animal producers are

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An investigation into the effect of temperature on the rate of respiration in yeast

An investigation into the effect of temperature on the rate of respiration in yeast There are two types of respiration in yeast: Aerobic: Anaerobic: Glucose Carbon dioxide + ethanol + energy Respiration is controlled by enzymes, which are proteins which speed up one or more biological reactions. Within any cell many chemical reactions are going on at any one time. Yeast has many different types of enzymes that speed up respiration. Prediction I predict that as temperature increases, the rate will also increase, until a certain optimum temperature, after which, the rate will decrease until the rate is zero as respiration has stopped completely. REASON As temperature increases, rate of respiration increases, because particles move faster and with more energy, which in turn means more particles collide with enough energy to react. However, as temperature increases, enzyme stability decreases, so at temperatures above the optimum temperature, the rate will decrease, until all the enzymes have been fully denatured and all the active sites have been lost. Enzymes speed up reactions in organisms. Each enzyme works on a specific substance, called its substrate. The diagram below shows an "E" (an enzyme) catalysing the breakdown of "S" (the substrate) into two different products ("P"). Catalysis occurs because substance S fits precisely into surface of the enzyme E, so this

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science case study

Contents page introduction 2 scientific theory 3 for mmr vaccines 4 against mmr vaccines 5 conclusions 6 Bibliography Introduction My case study is about how safe are mmr vaccinations and the reason's for and against the use of compulsory vaccinations. The way my case study is structured is the introduction firstly and the scientific theory ( the science behind mmr vaccination) thirdly the reasons for mmr vaccinations also the reasons against mmr vaccinations I will also include my opinion in the conclusion and finally a bibliography Scientific theory The MMR vaccine is an injection that prevents you from catching the following diseases. In the UK it is given to children at 12 to 15 months old, with a reinforcing dose (a booster) before school, usually between 3 and 5 years. * Measles - this can cause ear infections, pneumonia, fits and encephalitis (inflammation of the brain). Sometimes it can be fatal. * Mumps - this can cause meningitis, which can result in deafness. It may cause inflammation of the pancreas, leading to pain, nausea and vomiting. In boys it can damage the testicles and cause infertility. * Rubella - this is also known as German measles and is usually a minor illness. However, it's harmful to pregnant women. If you become infected during the first 10 weeks of pregnancy, it's very likely to cause problems in your unborn baby. These

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