Niche--Biology

Palak Shah TA: Luca BIO 101 The niche is one of the most significant concepts in ecology. An organism's niche is how it makes a living: the important resources it needs to survive and its ways of obtaining those resources. Competition occurs when organisms in the same community look for the same limiting resource. This resource may be water, prey, nutrients, light, etc. Competition with members of the same species is intraspecific. Competition with individuals of different species is interspecific. Individuals experience both types of competition, but the relative importance of the two types of competition varies from population to population and species to species. Exploitation competition may cause the elimination of one species. For this to happen, one organism must require less of the limiting resource to survive. The dominant species must also reduce the quantity of that resource below some critical level where the other species would be unable to replace its numbers by reproduction. Exploitation will not always cause the elimination of one species. They may coexist with a decrease in their potential for growth. Neutralism is the most common type of interspecific interaction. Neither population affects one another nor are any interactions that do occur indirect or incidental. Amensalism is when one species suffers and the other interacting species experiences no

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Should a DNA profile be taken at birth?

A DNA profile should be taken from each newborn baby. "DNA profiling (also called DNA testing, DNA typing, or genetic fingerprinting) is a technique employed by forensic scientists to assist in the identification of individuals on the basis of their respective DNA profiles."1 Within a clinical context DNA profiling has many potential human uses; immigration applications, determining adopted siblings, paternity testing and of course criminal justice. Limitations of the procedure include; it can only give statistical probable data, it is ethically wrong according to some experts, this then reliable source will be easy to plant in crime scenes and of course minorities may abuse DNA manipulation.2 DNA profiling at its current state is a tool used to gather circumstantial evidence, within the forensic and healthcare fields. Without scientific thought this process is a revelation but many ethical issues including human rights have been foreshadowed. Should a DNA profile be taken from each newborn baby? Deoxyribonucleic acid (DNA) is the cornerstone for human genic makeup, which serves as an instruction manual and blueprint for everything in your body. The process of electrophoresis is used to gather 'non coding DNA' (areas of short tandem repeats, STRs) using restricting enzymes. There are two common methods of separation and detection, capillary electrophoresis and gel

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Effect of exercise on heart rate and arterial blood pressure in young healthy volunteers.

59228 Physiological Basis of Drug Action II |Lab Report Effect of exercise on heart rate and arterial blood pressure in young healthy volunteers. **** **** ? 200636232 Effect of exercise on heart rate and arterial blood pressure in young healthy volunteers. Abstract Background and purpose: The aim of this experiment was to test the effect of mild exercise on heart rate, systolic blood pressure and diastolic blood pressure in young healthy adults. It was hypothesised that heart rate, systolic blood pressure and diastolic blood pressure would increase as it was already known that heart rate increased, pumping more blood throughout the body. It was suggested that the body's requirement for oxygen would cause all 3 values to increase. Experimental approach: Six healthy students had their heart rate and blood pressures read, and then each cycled at a steady pace for 5 minutes. The heart rate and blood pressures were measured immediately after this mild exercise session, and taken again after a 10 minute recovery period. Key results: It was found that heart rate increased dramatically between the rest state and immediately after exercise. After 10 minutes, it had decreased to around the same as the rest state. Systolic blood pressure increased after exercise, and decreased slightly below resting systolic pressure after the recovery period. Diastolic blood pressure

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Proprioception and the stretch refle

BM2037 - Physiology Practical Shell C Series C Practical 3 "Proprioception and the stretch reflex" Introduction The Effect of varying Weight loads on electrical activity Skeletal muscle is an organ within the body, which is primarily specialized for contraction. It is composed of many muscle fiber cells, which are an essential element of the skeletal muscle itself, and is supported by connective tissue which surrounds these fibres. It is found attached to bones by the means of tendons and is stimulated by somatic motor neurons. Skeletal muscles are greatly supplied with many nerves and blood vessels. The somatic neurons located within skeletal muscle extend from the brain or spinal cord and conclude at a group of muscle fibres. These nerve cells then branch numerous times so that each branch is able to extend to a different fiber. The capillaries that supply the muscle with oxygen and nutrients also remove heat and waste products generated by muscle metabolism, and are found in abundant quantities. The plasma membrane of a skeletal muscle fiber is called the sarcolemma and it contains many tubules known as transverse tubules. This is the site in which muscle action potentials travel along, rapidly spreading throughout the muscle fiber. Also within the sarcolemma is the sarcoplasm which is the cytoplasm of the muscle fiber. Large amounts of glycogen can be found

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Effect of Isotonic Exercise on HR and BP

Introduction With regular exercise a person's cardiovascular fitness can be immensely increased as cardiac output is increased, therefore enabling a greater rate of O² being delivered to the body's tissues. In cases of strenuous exercise, such as with athletes, the cardiac output is found to be double that of a person doing very little exercise, resulting in the enlargement of the heart and increasing the stroke volume. During isotonic exercise muscle contractions remain almost constant while the muscle may change in length. As a result of exercise, heart rate increases as the demand for oxygen has been made greater. This is achieved by the means of two different mechanisms. The first of these mechanisms is the psychological effect as the body prepares itself for the task ahead. The increase of ventilation as a result of anticipation of exercise is known as the neural changes which send excitatory impulses to the inspiratory area in the medulla oblongata in the brain. Stimulation of the limbic system also occurs as the body begins to prepare itself. Heart rate increases to ensure that enough blood is being pumped around the body. This initial response to the impending exercise is equivalent to that of the "fight-or-flight" response. Nerve impulses, initiated from the hypothalamus in the brain are sent to the sympathetic division of the ANS, which then starts to

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Lab report: food dehydration. This experiment focuses on the follow four questions: 1, to calculate the moisture contents on the dry basis of carrot and potato samples; 2, to assess the possible influence of pre-dehydration such as blanching on the qua

Lab report: food dehydration . Introduction In food preservation, dehydration is a common used approach. It is one of the oldest but also a simple and safe way to preserve food. It is process to remove moisture or water away from food. In a low moisture environment, yeast, bacteria and mold cannot grow (Andress and Harrison, 2006). Therefore, dehydration is helpful to minimize the growth of microorganism that is a major reason of food deterioration. At the meantime, drying also reduces the activity of enzymes that cause degradation of some nutrients. For fruit and vegetables that contain high level of water, they can go bad easily if inappropriate storage approach is applied. It was estimated 25-30% of total fruits and vegetable produced is wasted due to spoilage (Ramaswamy and Marcotte, 2006). Furthermore, dehydrated food is usually smaller and lighter and thus is convenient to transfer or store. There are several ways to achieve dehydration in industrial production, such as heat, dry air, air movement, in the sun, in the oven and using a food dehydrator (Ramaswamy and Marcotte, 2006). For some kinds of food, pretreatment such as blanching is required. Blanching which is a process of briefly precooking of food in steam or boiling water is helpful to reduce activity of enzymes, to skill spoilage organisms and to shorten drying time. However, beside the time of storage,

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According to researchers at the Center for Genomic Regulation, disruption of the circadian rhythm (the bodys natural biological clock) increases skin cells susceptibility to forming tumors and aging quicker due to the lack of cell regenera

Rob Ranson 4 November 2011 Circadian Rhythm and the Skin A recent study has revealed the importance of the body's circadian rhythm in the aging process and the regenerative capacity of skin stem cells. According to researchers at the Center for Genomic Regulation, disruption of the circadian rhythm (the body's natural biological clock) increases skin cells' susceptibility to forming tumors and aging quicker due to the lack of cell regeneration. The study, which was popularized by ScienceDaily, shines light on the importance of having a balanced sleep schedule -- something that, as a stressed college student, I seldom have the privilege to maintain. It also raises the question of just how important having a balanced circadian rhythm is, and how adverse the absence of one can be. Because stem cells regulate cell replacement in tissues, they constantly reproduce cells to replenish those that have deteriorated through daily use. Correctly functioning stem cells are essential for supporting healthy tissue, including dermal tissue, during the life of an organism. Every day, skin cells are exposed to various harmful agents such as ultraviolet rays and pathogens. The function of the skin is to protect from such dangers, while being an impermeable barrier that separates the inside of the body from the outside world. The study showed that when a circadian rhythm is interrupted,

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What causes Anorexia

What causes Anorexia? For people with anorexia, it really is true that one can never be too thin. Despite being dangerously underweight, anorexics see a fat person when they look in the mirror. What they don't see is the tremendous physical and emotional damage that self-starvation inflicts, so they continue to diet, fast, purge, and over-exercise. While people with anorexia often deny having a problem, the truth is that anorexia is a serious and potentially deadly eating disorder. Fortunately, recovery is possible. With proper treatment and support, you or someone you care about can break anorexia's self-destructive pattern and regain your health and happiness. What exactly is anorexia nervosa? An example; (Maria's Story) Seventeen-year-old Maria has been on one diet or another since she was in junior high. She recently lost 10 pounds from an already slender frame after becoming a strict vegetarian. Her parents are concerned about the weight loss, but Maria insists that she's just under stress at school. Meanwhile, her vegetarian diet is becoming stricter by the day. Maria obsessively counts calories, measures food portions, and weighs herself at least twice a day. She refuses to eat at restaurants, in the school cafeteria, or anywhere else in public, and she lives on salad dressed with vinegar, rice cakes, and sugar-free Jell-O. Maria also has a large stash of

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Superbugs the rise and fall of hospital acquired infections

Superbugs- the Rise (and fall?) of hospital acquired infections During the course of this essay the most common infections will be looked at. These include Methicillin Resistant Staphylococcus aureus (MRSA), Clostridium difficile (C.difficile), and Vancomycin-resistant Enterococcus faecium (VRE). The development of drug resistance will also be outlined, and whether or not there has been an increase or a fall in the amount of cases. In addition the current problems will be examined, and strategies for control and prevention will be discussed. Hospital acquired infections usually occur 48 hours or more after hospital admission or within 30 days after discharge. This type of infection is also known as nosocomial infection. 2.8 million People in the U.K acquire a nosocomial infection from hospital each year, 90 000 of which die (Gould, 2005). A large number of infections that people acquire in hospitals are resistant to antibiotics, they are termed superbugs. One of the main types of infection is C. difficile, it is resistant to most antibiotics (McBryde et al, 2004). Antibiotics disrupt the normal intestinal flora causing the bacteria to become overgrown instigating severe diarrhea. C. difficile produces heat-resistant spores that remain on hospital surfaces for a long period of time. Once the spores are ingested, they pass through the stomach to the colon, where they

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Bi technology and food security: The clue for a new green revolution?

BITECHNOLOGY AND FOOD SECURITY: THE CLUE FOR A NEW GREEN REVOLUTION? RURAL PRODUCTION SYSTEMS TANIA MARTIN CRUZ APRIL 2002 INTRODUCTION Biotechnology is a new revolution; it has the power to modify DNA in living organisms in order to achieve the required results. With biotechnology genetic engineering has reached a powerful status, it means that human beings can adapt living organisms to their necessities or desires. My goal has been to analyse biotechnology and specifically Genetic Modified Crops (GM crops), to know if they can be the tool for a New Green Revolution. A revolution that will be able to provide food security to the poor in developing countries, to use the potential benefits of biotechnology to prevent hunger and poverty, to improve the nutritional status of food or make them adaptable to specific weather conditions among other properties. To achieve this I have analysed the principal points of view about biotechnology, their objectives, benefits and risks and from this I have developed my own arguments about biotechnology and food security. My assumption and the arguments given are addressed to demonstrate that biotechnology could be a potential tool to improve food security but the actual companies being managed to develop researches on biotechnology are not considering food security as one of the main goals, on the contrary, they are adapting

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