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Ch.1 - Introduction: Matter, Energy, and Measurement
Chapter 1, Problem 88

In 2005, J. Robin Warren and Barry J. Marshall shared the Nobel Prize in Medicine for discovering the bacterium Helicobacter pylori and for establishing experimental proof that it plays a major role in gastritis and peptic ulcer disease. The story began when Warren, a pathologist, noticed that bacilli were associated with the tissues taken from patients suffering from ulcers. Look up the history of this case and describe Warren’s first hypothesis. What sorts of evidence were required to establish a credible theory based on it?

Verified step by step guidance
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Step 1: Begin by researching the history of the discovery of Helicobacter pylori, focusing on the work of J. Robin Warren and Barry J. Marshall.
Step 2: Identify Warren's initial observations, particularly his hypothesis that the presence of bacilli (bacteria) was linked to gastric ulcers.
Step 3: Explore the types of evidence Warren and Marshall needed to gather to support their hypothesis, such as clinical studies, laboratory experiments, and patient case studies.
Step 4: Investigate how Warren and Marshall demonstrated the causative role of Helicobacter pylori in gastritis and peptic ulcer disease, including any experimental methods they used.
Step 5: Summarize the process by which their hypothesis was accepted by the scientific community, noting any challenges or breakthroughs that were pivotal in establishing a credible theory.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Helicobacter pylori

Helicobacter pylori is a gram-negative bacterium that colonizes the stomach lining and is linked to various gastrointestinal diseases, including gastritis and peptic ulcers. Its discovery was pivotal in understanding the microbial causes of these conditions, challenging the long-held belief that stress and diet were the primary factors. The bacterium's ability to survive in the acidic environment of the stomach is a key feature that contributes to its pathogenicity.

Hypothesis Formation

A hypothesis is a proposed explanation for a phenomenon, serving as a starting point for further investigation. In Warren's case, his initial hypothesis suggested that the presence of Helicobacter pylori in ulcer patients was causally linked to the development of ulcers. This hypothesis required rigorous testing and evidence to be validated, including controlled experiments and clinical observations.
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Enthalpy of Formation

Evidence in Scientific Research

Establishing a credible scientific theory requires robust evidence, which can include experimental data, observational studies, and reproducibility of results. In the case of Helicobacter pylori, evidence such as the isolation of the bacterium from ulcer patients, its ability to induce ulcers in animal models, and the successful treatment of ulcers with antibiotics were crucial in supporting Warren's hypothesis. This multifaceted approach helped solidify the bacterium's role in ulcer disease.
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Scientific Notation Concepts
Related Practice
Textbook Question
A 40-lb container of peat moss measures 14 * 20 * 30 in. A40-lb container of topsoil has a volume of 1.9 gal. (b) How many bags of peat moss are needed tocover an area measuring 15.0 ft * 20.0 ft to a depth of 3.0 in.?
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Textbook Question
The total rate at which power is used by humans worldwideis approximately 15 TW (terawatts). The solar flux averagedover the sunlit half of Earth is 680 W>m2 (assumingno clouds). The area of Earth's disc as seen from the Sun is1.28 * 1014 m2. The surface area of Earth is approximately197,000,000 square miles. How much of Earth's surfacewould we need to cover with solar energy collectors to powerthe planet for use by all humans? Assume that the solar energycollectors can convert only 10% of the available sunlightinto useful power
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Textbook Question

Gold is alloyed (mixed) with other metals to increase its hardness in making jewelry. (a) Consider a piece of gold jewelry that weighs 9.85 g and has a volume of 0.675 cm3. The jewelry contains only gold and silver, which have densities of 19.3 and 10.5 g/cm3, respectively. If the total volume of the jewelry is the sum of the volumes of the gold and silver that it contains, calculate the percentage of gold (by mass) in the jewelry. (b) The relative amount of gold in an alloy is commonly expressed in units of carats. Pure gold is 24 carat, and the percentage of gold in an alloy is given as a percentage of this value. For example, an alloy that is 50% gold is 12 carat. State the purity of the gold jewelry in carats.

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