...Tanner Rackow DNA Assignment The scientists Oswald Avery, Colin MacLeod, and Maclyn McCarty all contributed to proving that DNA is genetic material. In their experiment involving treptococcus pneumoniae, the bacteria that causes pneumonia, they observed a factor which they called the “transforming principle.” Mice were injected with a harmless version of the bacteria as well as an inactive lethal form. Despite the predictions of the mice remaining healthy, the mice soon succumbed to disease and died. The coatings of the two bacteria varied. The deadly one had a smooth outer coating that would be undetected by the mouse’s immune system, whereas the other form had a rough coating and was destroyed by the immune system. The scientists questioned...
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...plasma membrane. Meanwhile, a new cell wall arising from the contents of the cell plate has formed between the daughter cells. 7. Eukaryotic cells have a true nucleus, bound by a double membrane Prokaryotic cells have no nucleus. Eukaryotic DNA is linear; prokaryotic DNA is circular (it has no ends). Eukaryotes go through every phase of Mitosis including prophase, metaphase, anaphase, and telophase. Prokaryotic cell simply divides by cytokinesis after DNA replication which is known as binary fission. 8. Checkpoints make sure that the eukaryotic cell completes each phase with no problems. Without checkpoints it may affect cell growth which is very important. 9. The Hershey-Chase experiments by Alfred Hershey and Martha Chase helped confirm DNA as genetic material. Using bacteriophages, Hershey and Chase added radioactive elements into the bacteriophages by adding the isotopes. The phage coats remained on the outside of the bacteria, while genetic material entered. Centrifugation allowed for the separation of the phage coats from the bacteria. These bacteria were lysed to...
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...In 1952, Martha Chase and Alfred Hershey were able to prove that DNA is the genetic material of the phage T2. The T2 phage consists almost entirely of DNA and protein, it also attacks E. Coli (, a common intestinal bacteria of mammals). The T2 phage quickly turns an E. coli cell into a T2-producing factory that releases phages whenever the cell ruptures. To determine what the source of the genetic material is in the phage, Hershey and Chase designed an experiment in which they labeled the protein or the DNA and then tracked what entered the E. coli cell during infection. They grew one batch of the T2 phage in the presence of the radioactive sulfur, marking only the proteins but not the DNA. They grew another batch but this time with the presence...
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...molecule to be able to carry genetic information.” Proteins seemed stronger for storing genetic information and “fit the requirements for heredity.” However, despite this theory, scientist have conducted experiments to inform that DNA actually carries genetic information. In 1928, Frederick Griffith experimented on the bacteria Streptococcus pneumoniae, which causes pneumonia in humans on mice. Griffith used two strains of bacteria, R and S. Bacteria S, named after it’s smooth appearance had an outer capsule which protected it from the mouse immune system causing it to be pathogenic. (disease-causing) Bacteria R, having a rough appearance lacking a capsule and nonpathogenic (harmless). Griffith injected mice with heat bacteria S, which did not kill mice. Griffith combined bacteria R with heat bacteria S to inject into a mouse, which killed the mouse. He also discovered the bacteria R has changed into a bacteria S. Griffith conclude his results as the “transforming principle”, creating the term transformation. Transformation is the process in which one strain of bacteria is changed by a gene or genes from...
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...Section B 1. A) What properties of chromosomes suggested to early geneticists that they might harbor the genetic material? What experiments confirmed these suspicions? Chromosomes was known to possess deoxyribonucleic acid. The genetical material was expected to have the stability but still capable of accepting sudden and permanent changes to adapt to evolution. Experiments that confirmed the suspicions were done by: • Griffith- demonstrated non-virulent strains of bacteria turned virulent when mixed with heat-killed pathogenic bacteria • Avery and colleagues- showed that deoxyribonuclease leads destruction of transforming activity • Hershey and Chase- used radioactive labels and bacteriophages to show that only nucleic acid was passed onto progeny not protein B)...
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...Deoxyribonucleic acid makes up our genetics. It’s located in the nucleus of all cells. DNA is made up of deoxyribose sugar, a phosphate, and nitrogen base. There are four bases adenine, thymine, guanine, and cystone when paired up together (AT, CG) they start to make up a the shape of a twisted ladder (double helix) with sides made of alternating sugars and phosphates. The rungs (base pairs) or steps of the ladder are pairs of nitrogen bases. DNA has the information or instructions for building all of the cell's proteins. The proteins handle everything else. Alfred Hershey and Martha Chase discovered, through a series of experiments, in 1952 that DNA was made of genetic material. Before their discovery, most scientists had thought that proteins were the element that carried all genetic material. The confirmation that it was DNA that carried genetic material paved the way for a lot of advances in genealogy ,forensic science and the study of genetics to determine inherited diseases. Erwin Chargaff discovered what we know ar “Chargaff’s rules.” The first rule was that the number of guanine bases equals the number of cytosine bases, and that the number of adenine bases equals the number of thymine bases. The second rule was that the DNA varied from species to species. Rosalind Franklin helped in understanding the structure of the DNA by discovering the A and B forms of the DNA. She had applied the technique of x-ray diffusion in conducting her research. Franklin had figured...
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...are features that are transmitted genetically from parents to their children or offspring. DNA or genetics was first discovered in 1869 by Friedrich Miescher after finding a phosphorus matter inside of the nuclei which was named deoxyribonucleic acid. DNA is a self-replicating material and is present in all living organisms. It is the carrier of genetic information. This report will be explore the ideas of scientists that help form our current understanding of DNA as well as comparing their ideas to others. Throughout history many scientist have made discoveries that contributed to our current understanding today. In this report we will be comparing the findings and technology of Walter Sutton, Thomas Hunt Morgan, Oswald Avery and Alfred Hershey....
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...viruses is false? A) A virus is generally considered to be alive because it is cellular and can reproduce on its own. B) The host cell provides most of the tools and raw materials for viral multiplication. C) Once a person is infected with the herpesvirus, the virus remains permanently latent in the body. D) Viruses can enter a host cell when the protein molecules on the outside of the virus fit into receptor molecules on the outside of the cell. E) Herpesviruses and the virus that causes AIDS can remain latent inside our cells for long periods of time. Answer: A Topic: Opening Essay Skill: Factual Recall 2) Which of the following people conducted the experiments that demonstrated that DNA is the genetic material of bacteriophages? A) Watson and Crick B) Hershey and Chase C) Franklin D) Griffith E) Pauling Answer: B Topic: 10.1 Skill: Factual Recall 3) One type of virus that infects bacteria is called a A) phage. B) mage. C) rhinovirus. D) filovirus. E) coronavirus. Answer: A Topic: 10.1 Skill: Factual Recall 4) When a T2 bacteriophage infects an Escherichia coli cell, which part of the phage enters the bacterial cytoplasm? A) the whole phage B) only the RNA C) only the DNA D) the protein "headpiece" and its enclosed nucleic acid 2 E) the tail fibers Answer: C Topic: 10.1 Skill: Factual Recall 5) The way that genetic material of a bacteriophage enters a bacterium is most like the way that...
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...Genetic Engineering Wesley Rupe, Jawad Rana, Layli Stroia, Charles Taiwo, Mariella Velasquez, Mark Young DeVry University Genetic Engineering Table of contents Title page ………………………………………………………………………………………………………………………. 1 Table of contents ……………………………………………………………………………………………………………. 2 1. A brief description of the technology and an explanation of the associated science (Mariella Velasquez) ………………………………………………..……………. 3 2. Psychological considerations and sociological effects (Mariella Velasquez) …………. 3 3. The historical development and context of the technology (Wesley Rupe) …………. 13 4. Political and legal influences (Mark Young) (Not Complete) 5. Economic questions and considerations (Jawad Rana)………………………………….…… 21 6. The technology in its cultural context, media influence (Charles Taiwo) (Not Complete) 7. Implications for the environment (Charles Taiwo) (Not Complete) 8. Moral and ethical implications (Layli Stroia) ……………………………………………………..… 30 Outline A brief description of the technology and an explanation of the associated science Definition: What is Genetic Engineering? Genetic engineering (GE) is the process of manipulation of an organism genome to create a new DNA. The new DNA might be implanted in a totally different DNA species. It is widely used to create hybrids (some species are not able to naturally breed), correct genetic flows in any type of being. It is applied in...
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...Section A: Basic Microbiology 1 SCOPE AND HISTORICAL DEVELOPMENTS IN MICROBIOLOGY “Science contributes to our culture in many ways, as a creative intellectual activity in its own right, as a light which has served to illuminate man’s place in the uni-verse, and as the source of understanding of man’s own nature” —John F. Kennedy (1917–63) The President of America The bacterium Escherichia coli INTRODUCTION AND SCOPE MICROBIOLOGY is a specialized area of biology (Gr. bios-life+ logos-to study) that concerns with the study of microbes ordinarily too small to be seen without magnification. Microorganisms are microscopic (Gr. mikros-small+ scopein-to see) and independently living cells that, like humans, live in communities. Microorganisms include a large and diverse group of microscopic organisms that exist as single cell or cell clusters (e.g., bacteria, archaea, fungi, algae, protozoa and helminths) and the viruses, which are microscopic but not cellular. While bacteria and archaea are classed as prokaryotes (Gr. pro-before+ karyon-nucleus) the fungi, algae, protozoa and helminths are eukaryotes (Gr. eu-true or good+ karyon-nucleus). Microorganisms are present everywhere on earth, which includes humans, animals, plants and other living creatures, soil,water and atmosphere. Microorganisms are relevant to all of our lives in a multitude of ways. Sometimes, the influence of microorganisms on human life is beneficial, whereas at other times, it is detrimental. For example...
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...Virtual Teams: A Review of Current Literature and Directions for Future Research1 Anne Powell Southern Illinois University Edwardsville Gabriele Piccoli Cornell University Blake Ives University of Houston Abstract Information technology is providing the infrastructure necessary to support the development of new organizational forms. Virtual teams represent one such organizational form, one that could revolutionize the workplace and provide organizations with unprecedented levels of flexibility and responsiveness. As the technological infrastructure necessary to support virtual teams is now readily available, further research on the range of issues surrounding virtual teams is required if we are to learn how to manage them effectively. While the findings of team research in the traditional environment may provide useful pointers, the idiosyncratic structural and contextual issues surrounding virtual teams call for specific research attention. This article provides a review of previously published work and reports on the findings from early virtual team research in an effort to take stock of the current state of the art. The review is organized around the input – process – output model and categorizes the literature into issues pertaining to inputs, socio-emotional processes, task processes, and outputs. Building on this review we critically evaluate virtual team research and develop research questions that can guide future inquiry in this fertile are of inquiry. ACM Categories:...
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...USA $25.95 CANADA $27.95 • W h y do our headaches persist after taking a one-cent aspirin but disappear when we take a 50-cent aspirin? • Why does recalling the Ten Commandments reduce our tendency to lie, even when we couldn't possibly be caught? • W h y do we splurge on a lavish meal but cut coupons to save 25 cents on a can of soup? • W h y do we go back for second helpings at the unlimited buffet, even when our stomachs are already full? • And how did we ever start spending $4.15 on a cup of coffee when, just a few years ago, we used to pay less than a dollar? hen it comes to making decisions in our lives, we think we're in control. We think we're making smart, rational choices. But are we? In a series o f illuminating, often surprising experi ments, M I T behavioral economist Dan Ariely refutes the common assumption that we behave in fundamentally rational ways. Blending everyday experience with ground breaking research, Ariely explains how expectations, emotions, social norms, and other invisible, seemingly illogical forces skew our reasoning abilities. N o t only do we make astonishingly simple mistakes every day, but we make the same types of mistakes, Ariely discovers. We consistently overpay, underestimate, and procrastinate. We fail to understand the profound effects of our emotions on what we want, and we overvalue what we already own. Yet these misguided behaviors are neither random nor senseless. They're systematic and predict able—making us predictably irrational...
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...Biology guide First assessment 2016 Biology guide First assessment 2016 Diploma Programme Biology guide Published February 2014 Published on behalf of the International Baccalaureate Organization, a not-for-profit educational foundation of 15 Route des Morillons, 1218 Le Grand-Saconnex, Geneva, Switzerland by the International Baccalaureate Organization (UK) Ltd Peterson House, Malthouse Avenue, Cardiff Gate Cardiff, Wales CF23 8GL United Kingdom Website: www.ibo.org © International Baccalaureate Organization 2014 The International Baccalaureate Organization (known as the IB) offers four high-quality and challenging educational programmes for a worldwide community of schools, aiming to create a better, more peaceful world. This publication is one of a range of materials produced to support these programmes. The IB may use a variety of sources in its work and checks information to verify accuracy and authenticity, particularly when using community-based knowledge sources such as Wikipedia. The IB respects the principles of intellectual property and makes strenuous efforts to identify and obtain permission before publication from rights holders of all copyright material used. The IB is grateful for permissions received for material used in this publication and will be pleased to correct any errors or omissions at the earliest opportunity. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted...
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...Virtual Teams: A Review of Current Literature and Directions for Future Research1 The DATA BASE for Advances in Information Systems Anne Powell Southern Illinois University Edwardsville Gabriele Piccoli Cornell University Blake Ives University of Houston Winter 2004 (Vol. 35, No. 1) Introduction Global competition, reengineered product life cycles, mass customization, and the increased need to respond quickly to customers’ needs are just some of the more pronounced trends currently driving organizational change (Grenier & Metes, 1995; Miles & Snow, 1986; Miles & Snow, 1992). One of the building blocks of these successful organizations is the Virtual Team. As a consequence, a growing number of organizations are implementing them or plan to implement them in the near future (Lipnack &Stamps, 1997; McDonough et al., 2001) and their use is expected to continue to grow (Carmel & Agarwal, 2001; McDonough et al., 2001). The increasing popularity of virtual teams has spurred a parallel growth in research examining various aspects of virtual team adoption and use. Recent research has studied virtual team inputs, socioemotional processes, task processes, and outcomes. Much of this literature focuses on comparisons of virtual teams and traditional teams. Virtual Teams Traditionally, both the terms “team” and “group” have been used to describe small collections of people at work. While the two terms are often used interchangeably...
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