WHAT IS LIFE? I hoped that the dictionary would offer some help in response to this cryptic question, but sadly it did not. The numerous dictionary definitions of life do very little to explain what life is and many people have varying opinions on what is and what is not alive. However I do I certainly agree with Antonio Lazcano who stated that "An all embracing, generally agreed upon definition of life has proven to be an elusive intellectual endeavour". So whilst it is unlikely that I will solve the question 'What is Life?' in this essay, I will attempt to explore some of the fundamental characteristics of life and the uncertain boundaries between what is alive and what is not. Many of us are taught that life is plainly defined by 'MRS GREN'; (Movement, Reproduction, Sensitivity, Growth, Respiration, Excretion and Nutrition); however this is a vast simplification of the topic. The answer to 'What is Life?' is unequivocally ambiguous which is highlighted by the distinct lack of scientific agreement. In addition, philosophers and theologians confuse the matter, contemplating over things such as robotic and computer life and the 'self-aware internet'. It seems that any attempts to define life are doomed to failure due to the simple fact that the transition from the complex organic molecules (which were existent between 1 and 2 billion years ago on earth) to primitive, living
Problem/Solution Paper Trenton Albrecht Death and Disease From Dining Contrary to what most people think, problems with American food are a large cause of disease and death in the United States. Most people underestimate the strength of diseases such as E. Coli that are spread through food and affect many Americans every year from the lack of a genuine solution to prevent it. Although many problems can be found with the safety of food in America today, especially regarding cattle, much can be done to improve the situation. General food safety problems affect many people. In fact, eighty million Americans will get sick because of what they eat per year. Of those eighty million, 325,000 will be hospitalized, and 9,500 will die. One of the common diseases found in American food is salmonella, which occurs in poultry. Four million Americans will get sick from it, and five hundred will die from it each year. In addition to salmonella, Escherichia coli O157:H7, also known as E. Coli, is a bad disease that is found in meat, comes from cow feces and can infect people with only a few organisms. More outbreaks have been traced to ground beef with E. Coli than with any other food. To illustrate, an estimated twenty thousand Americans will get sick from it, and five hundred will die from it each year. Also, five percent of cattle have E. Coli, and ten percent of
A good quality image is the key factor to a successful abdominal x-ray. There are many scientific principles involved in the production of an x-ray image which can be controlled by the operator. Although exposure factors can be varied and altered in different aspects, the abdominal x-ray is much more limited in diagnosis than a basic chest x-ray. (Bicklem, I 2006) The supine abdominal x-ray is the standard for an x-ray. (Kelly, B. 2002). The supine postion for abdominal x-rays is used 99% of the time. The abdominal radiograph is one of the most commonly requested images. X-rays of the supine abdominal postion are past from front to back. (Kelly, B. 2002). The supine positon is more appropriate to demonstrate objects. (Ball, C and Price, T 1995). It is important to manipulate the exposure factors in order to produce the best quality image. The quality of the beam indicates its penetrating power. Knowlodge of these factors assist the radiographer in achieving the best quality image possible. Ball, C and Price, T 1995). When taking a successful abdominal x-ray, it is important to focus on the patient in relation to the controlling factors. There is no advance preparation required. The radiographer should get the patients history as they may determine exposure factors or inidcate any varitations that may be needed. The patient lies in a supine position (facing upwards).
Comparison of the structural and functional specialisations of cells lining the stomach with those of the cells lining the small intestine.
Page 1 Comparison of the structural and functional specialisations of cells lining the stomach with those of the cells lining the small intestine. The specialised cells lining the stomach and small intestine vary in structure and function; however, they are similar in the fact that they are both involved in the digestion process. The stomach is a j shaped organ with a wall of muscle which has lots of folds called rugae to enable the stomach to expand when food is present. There are three types of specialized stomach cells that are located in the glands of the stomach lining which is called the mucosal epithelium. These cells produce various gastric secretions necessary for the breaking down food into a soup like liquid called chyme. When this is complete, chyme is passed via the pyloric sphincter into the small intestine which continues digestion and absorbs nutrients into the blood stream or fats into the lymphatic system. The small intestine is approximately 7 metres long and is divided into three parts; the duodenum, jejunum and ileum. Its wall consists of 4 layers; the outer covering called the adventitia, muscularis externa, submucosa and mucosa (see diagram 1). The submucosa is a layer of connective tissue where blood and lymph vessels, glands and enteric ganglia are present. The enteric ganglia is a group of neuron cell bodies that stimulate the production
Will HIV and AIDS be seen as the black death of the 21st century? Human Immunodeficiency Virus (HIV) is seen by many as the "Black Death" of the 21st century, however, it is unlikly that it will have the detrimental effects that the Bubonic Plague had on society. I will state the many reasons why this should not be seen as such a drastic effect by exploring, the prevention, media,reconition, treatment and the primary cause's of these diseases. I will also explore the stigma behind H.I.V and AIDs which causes them to be seen as the Black Plague of the 21st century ie, death toll,drug resistance,denial,silent symptoms and the ongoing problems with treatment. AIDS is caused by the HIV virus it enters the body in numerous ways. The HIV virus is deadly because it seeks out and attacks white blood cells called T4 lymphocytes these are used to coordinate the body's immune defence system. Hubley, J. (1990). The Aids Handbook. pp 9-11. MACMILLAN PRESS LTD The HIV virus takes over these cells and uses DNA to replicate. The T4 cells then produce lots of HIV virus particles which break out instantly killing the T-lymphocyte cell. These copies of the virus then attach to any new T-lymphocyte cells that are created. For a while the body is able to keep the immune system working properly however there comes a point when the body is no longer able to keep up with virus and your
Agglutination & lysine of sheep red blood cells Introduction They are many uses in science for agglutination for example the determination of which blood group an individual belongs to. However agglutination is commonly the adhesion of particles. Biological agglutination occurs in the clumping of cells in response to an antibody, the adhesion of small particles that are suspended in a solution, which are then (usually) precipitated in allergic reactions, when cells clump together to prevent antigens from entering, Antigens are usually proteins or polysaccharides, that could be on bacteria, but not actually the bacteria it self. But in biology/immunology many agglutination experiments are carried out in order to identify antibodies, which are specified to go against cellular antigens. In the 1st part of the experiment we were given immune rabbit serum and non-immune rabbit serum which, was acting against sheep red blood cells as an antigen. The second part of the experiment was antibodies that produce lysins in the presence of a complement, which is similar to the agglutination process, and both processes are measured using the same technique. Aims & Objectives The main objective of this experiment was to observe what actually happens in the agglutination and lysis reactions, also to help us understand the processes more clearly, and to determine the agglutination and
Project Update #1 Stem Cells: Self-Renewal, Differentiation, and Heterogeneity Joe Buran, Nick Rotella, Karamveer Birthare Introduction- Stem cells are biological cells found in all multi-cellular organisms, and have the potential to develop into several different types of cells in the body during their early life and throughout growth. They also play a major role in the regeneration of many tissues, as they continue to divide almost without limit as long as the organism is still alive. After a stem cell divides, it can either remain a stem cell or continue to grow, or it can differentiate into a more specific cell with a specialized function. Heterogeneity of Stem Cells- The classical definition of a stem cell requires that it possesses two properties, or metastable cell states. The first property, self-renewal, means that they have the ability to go through numerous cycles of cell division while maintaining the undifferentiated state. Secondly, they must possess potency. This is the ability under certain physiological conditions to become, or differentiate, into tissue or organ-specific cells with defined tissues. However, in other areas and tissues of the body, stem cells may only divide under special biological conditions. The ability of a stem cell to maintain both metastable cell states is referred to as stem cell heterogeneity. Various groups of scientists have
Investigation Of The Respiratory Chain In Mitochndria. The experiments were carried out to investigate electron transport of the respiratory chain of yeast mitochondria and to examine the effects of different compounds on the chain. This was done using s
Introduction The experiments were carried out to investigate electron transport of the respiratory chain of yeast mitochondria and to examine the effects of different compounds on the chain. This was done using spectrometry and the absorbance spectral properties of a redox dye (DCPIP), which acts as an artificial electron donor/acceptor. Method For safety guidelines, the apparatus and the techniques employed when carrying out the experiment, see the attached, workshop handout. Results Results Table Experiment A Minutes Experiment 1 (Part 2) Absorbance Experiment 1 (Part 3) Absorbance Experiment 1 (Part 4) Absorbance Experiment 1(Part 5) Absorbance 0 0.96 0.95 0.91 0.54 0.5 0.96 0.95 0.895 0.54 0.96 0.95 0.87 0.54 .5 0.96 0.94 0.85 0.54 2 0.96 0.94 0.83 0.54 2.5 0.96 0.94 0.81 0.54 3 0.96 0.94 0.79 0.545 3.5 0.96 0.94 0.77 0.545 4 0.96 0.935 0.76 0.545 4.5 0.96 0.935 0.735 0.545 5 0.96 0.935 0.72 0.55 5.5 0.705 6 0.69 6.5 0.655 7 0.65 7.5 0.64 8 0.625 8.5 0.61 9 0.6 9.5 0.585 0 0.57 0.5 0.56 1 0.55 1.5 0.54 2 0.53 2.5 0.515 3 0.51 3.5 0.49 4 0.48 4.5 0.475 5 0.46 Results Table Experiment B Minutes Experiment B (Part 1) Experiment B (Part 2) Experiment B (Part 3) 0 0.91 0.84 0.75 0.86 0.84 0.61 2 0.81 0.83 0.54 3 0.77 0.825 0.52 4 0.73 0.825 0.515
Mabel Akinwumiju Molecular Cell Biology Lab Due: December 4, 2007 TA: Xiaoli Zhang Group #6 Polymerase Chain Reaction Materials and Methods: In order to perform polymerase chain reaction, the following cocktail was made: DNA template, deoxynucleotide triphosphates (dNTP), Taq polymerase, two primers, and a buffer solution. Before starting the PCR, first four samples were collected from the prime suspects and 19 uL "cocktail" was added. 1 uL of DNA from each suspect was placed into separate tubes, then 89 uL dH20, 6 uL dNTP, 3ul of forward primer, 3 uL of reverse primer, 1 uL Taq polymerase, and 12 uL 10X PCR buffer was added into each eppendorf tube. After thoroughly mixing, the samples were placed into the PCR tubes and then placed into the thermocyler. After the PCR cycle was preformed 2 uL of tracking dye was added to each sample and then they each were loaded into 7% acrylamide gel in 1X TBE solution for gel electrophoresis. The gel was run for approximately 1 1/2 hours at 240 volts, and then the gel was placed in an ethidium bromide solution for 10 minutes to help stain the DNA. Then the TA photographed it under a UV light. Results: After the gel electrophoresis procedure was complete, we were able to generate the PCR result The figure on the picture found in the appendix depicts the results that were obtained from the gel electrophoresis done for the
Discuss the roles of the following in protein synthesis in mammalian cells:- the large and small subunits of the ribosome, mRNA, tRNA, release factors, SRP
Discuss the roles of the following in protein synthesis in mammalian cells:- the large and small subunits of the ribosome, mRNA, tRNA, release factors, SRP. Genes drive metabolism, growth and differentiation in living cells. They do this by promoting the synthesis of proteins which in turn catalyse many biological reactions. Therefore the synthesis of proteins is one of the most central and basic events in the life of every cell. The process of proteins synthesis is divided into two different parts; transcription and translation. Transcription is performed by RNA polymerase which uses one strand of the DNA helix as a template to synthesis messenger RNA (mRNA). This mRNA then migrates from the nucleus to the cytoplasm. Translation then occurs and according to Lodish et al (1995) this process is when the base sequence of the mRNA is used to order and to join the amino acids in the protein. To explain the roles of ribosomes, mRNA, transfer RNA (tRNA), release factors and signal recognition particles (SRP) the process of translation needs to be explained in more detail. The pathway of translation is divided into three main steps; initiation, elongation and termination. The mRNA has a protein coding region which is composed of a non-overlapping string of codons called an open reading frame. At the beginning of the open reading frame is a start codon and at the end there