...Week 1 – HOW LIFE WORKS: Biology – Science of How Life Works; study of life; attempt to understand processes of life. How life works - many levels. Three levels: -Molecular mechanisms within the cell -Integrated actions of many cells within an organ or body -Interactions among different organisms in nature Life Processes – Microscopic and macroscopic levels: All methods of scientific study use the Scientific Method Scientific Method – Systematic approach to finding out how things work. (i.e., structured and disciplined way to study things) Deliberate way of asking questions about things we don’t yet understand. Start with observation – Sensing the world around us with our 5 senses or with augmented abilities such as scientific instruments; – seeing a particular event or occurrence; Scientists then make proposed, tentative explanations < - - i.e., hypothesis (a predictive guess) and plan out detailed experiments or detailed observations to see if the tentative explanation is correct (i.e., true). Test that tentative explanation [pic] Make some observations of the image above. Ideas: -What motivates this behavior? -Is the bird feeding? -Does the bird choose this flower because of its color? -Does the flower benefit from the bird’s behavior? Observations made and the questions they raise allow us to propose tentative explanations, or hypotheses. ...
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...Pathogenicity All the various surface components of a bacterial cell are important in the ecology because they mediate the contact of the bacterium possesses result from immediate contact with its environment. Its must use its surface components to assess the environment and respond in a way that supports its own existence and survival in that environment. The surface properties of a membrane and cell envelope, including capsules, glycocalyx, slayers, peptidoglycan and lps, and the other surface structures, such as flagella and pili or fimbriae. Bacterial surface components may have a primary biological function that has nothing to do with path ogenicity. However, there are endless examples wherein a bacterial surface component plays an indispensable role in the pathogenesis of infectious disease. Bacterial structures may act as permeability barriers that allow selective passage of nutrients and exclusion of harmful substances; adhesions used to attach or adhere to specific surfaces or tissues; enzymes to mediate specific reactions on the cell surface important in the survival of the organism; protective structures against phagocytic engulfment or killing; antigenic disguises to bypass activation oh host immune defenses; endotoxins, generally cell wall components, that cause an inflammatory response in the host; “sensing proteins” that can respond to temperature, osmolality, salinity, light, oxygen, genome of the cell that will cause expression of some determinant of virulence. ...
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...University of Chicago, Chicago, Illinois, United States of America Summary: Recent cancer studies emphasize that genetic and heritable epigenetic changes drive the evolutionary rate of cancer progression and drug resistance. We discuss the ways in which nonheritable aspects of cellular variability may significantly increase evolutionary rate. Nonheritable variability arises by stochastic fluctuations in cells and by physiological responses of cells to the environment. New approaches to drug design may be required to control nonheritable variability and the evolution of resistance to chemotherapy. Cancer progression is a series of evolutionary changes. Those changes include enhanced cellular proliferation, reduced cellular death by abrogating normal apoptotic mechanisms, greater invasiveness by increased expression of proteases, and improved colonizing ability to achieve metastasis [1]. In response to drug treatment, cancer cells often evolve resistance and continue to spread. Each evolutionary step typically proceeds by acquisition of genetic or heritable epigenetic changes in cells. When does the novel genetic change arise in an evolutionary step? By the current view, rare genetic variants arise before widespread phenotypic change. The idea is that a novel phenotype always comes from a novel genotype [2,3]. For example, rare resistant genetic variants may exist before drug treatment [4]. The drug selects those rare resistant variants, killing the other cancer...
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...Stem cell technology overview In order to gain a better understanding of the many benefits as well as the concerns raised by stem cells research, it is important to first have a general idea of what stem cells are, along with the specific properties the different categories of stem cells possess that make them such a valuable commodity to modern medicine today. Stem cells contain human DNA, and as a result make up the basic building blocks of human organisms. This essentially gives them “unique regenerative abilities”. In that sense they are unspecialized cells “capable of dividing and renewing themselves” into most, if not all of the cell types found in the human body. Three different types of stem cells have been identified by scientists. Not necessarily in order of importance, they start from the embryonic group which carries the greatest potential for becoming any other cell types and as a result, the greatest subject of controversy. The other two types of stem cells are the adult stem cells, which are to a degree less useful and can only become one of a few cell types; and the induced pluripotent stem cells which are specially treated cells that can be processed to behave somewhat like embryonic stem cells. Induced pluripotent stem cells commonly abbreviated as iPS cells or iPSCs are a type of pluripotent stem cell artificially derived from a non-pluripotent cell - typically an adult somatic cell - by inducing a "forced" expression of specific genes. ...
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...has developed different mechanisms to survive the conditions in their environment. Through careful observation we have compiled the most likely combination of physiological adaptations for the Grindylows to thrive in their habitat. In order to survive in the conditions of the Black Lake, the Grindylow faces multiple challenges. Primarily, their living condition can be categorized into three phases; summer day, summer night and winter. During the summer days, the environment is hyperoxic(pO2>400mmHg) and hypocapnic(PCO2~0mmH) with temperatures up to 28 degrees Celsius. On the other hand, in summer nights the water becomes hypoxic(pO2~10mmHg) and hypercapnic(pCO2~25mmHg) with the same temperature....
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...engineering advances. Scientists can design and build DNA containing genes they want and then transfer these genes into bacterial cells that they can get to express those genes. This is a very basic technique that is used on a daily basis in a molecular biological laboratory. This is based on the natural function of a plasmid: to transfer genetic information vital to the survival of the bacteria. Transformation is an example of horizontal gene transfer. There are three mechanisms for horizontal gene transfer in bacteria. Conjugation is the transfer of DNA from one cell to another through conjugation pili. Transduction is the transfer of genes between bacterial cells using a bacteriophage (a type of virus). Transformation is the ability of cells to take up freely floating DNA found in the environment. Bacterial cells that are able to take up free-floating DNA from the environment are called competent cells. Bacteria are not always competent. When growth conditions are optimal, most bacteria cannot uptake DNA. In most cases, in response to some stimuli (such as stressor starvation), a cell can turn on the genes that allow it to become competent. In nature, as bacterial cells die, their cells are lysed, spilling their plasmid DNA into the environment. The DNA chromosome is broken up into chunks that float freely in the environment. A competent cell could take up one or more of the chunks. If a gene that is taken up is similar to a gene...
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...parts of the ocean and deep within Earth. They are in the soil, in our food, and on plants and animals. Even our bodies are home to many different kinds of bacteria. Our lives are closely intertwined with theirs, and the health of our planet depends very much on their activities. Bacterial cells are so small that scientists measure them in units called micrometers (µm). One micrometer equals a millionth of a meter (0.0000001 m or about 0.000039 in), and an average bacterium is about one micrometer long. Hundreds of thousands of bacteria would fit on a rounded dot made by a pencil. Bacteria lack a true nucleus, a feature that distinguishes them from plant and animal cells. In plants and animals the saclike nucleus carries genetic material in the form of deoxyribonucleic acid (DNA). Bacteria also have DNA but it floats within the cell, usually in a loop or coil. A tough but resilient protective shell surrounds the bacterial cell. Biologists classify all life forms as either prokaryotes or eukaryotes. Prokaryotes are simple, single-celled organisms like bacteria. They lack a defined nucleus of the sort found in plant and animal cells. More complex organisms, including all plants and animals, whose cells have a nucleus, belong to the group called eukaryotes. The word prokaryote comes from Greek words meaning “before nucleus”; eukaryote comes from Greek words for “true nucleus.” The study of bacteria is called bacteriology, a branch of microbiology. Bacteria inhabited Earth long before...
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...1. Every person has cancer cells in the body. These cancer cells do not show up in the standard tests until they have multiplied to a few billion. When doctors tell cancer patients that there are no more cancer cells in their bodies after treatment, it just means the tests are unable to detect the cancer cells because they have not reached the detectable size. 2. Cancer cells occur between 6 to more than 10 times in a person's lifetime. 3. When the person's immune system is strong the cancer cells will be destroyed and prevented from multiplying and forming tumors. 4. When a person has cancer it indicates the person has multiple nutritional deficiencies. These could be due to genetic, environmental, food and lifestyle factors. 5. To overcome the multiple nutritional deficiencies, changing diet and including supplements will strengthen the immune system. 6. Chemotherapy involves poisoning the rapidly-growing cancer cells and also destroys rapidly-growing healthy cells in the bone marrow, gastro-intestinal tract etc., and can cause organ damage, like liver, kidneys, heart, lungs etc. 7. Radiation while destroying cancer cells also burns, scars and damages healthy cells, tissues and organs. 8. Initial treatment with chemotherapy and radiation will often reduce tumor size. However prolonged use of chemotherapy and radiation do not result in more tumor destruction. 9. When the body has too much toxic burden from chemotherapy and radiation the immune...
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...element is always equal to the number the electrons. The number of neutrons may vary to make isotopes of that element. Elements come together to give up, accept or equally share electrons to make molecules. The smallest part of an organism is a cell. Some single-celled organisms are free-living and contain structures, called organelles that allow them to be self-sufficient. More complex organisms are multicellular. In the case of a human, cells are organized into tissues. These have a common function like a muscle. Tissues are organized into organs like the heart. Organs are organized into organ systems, like the cardiovascular system. Organ systems functioning together make up a living organism. A population is an organization of more than one individual. This is generally all of one species in a particular area. We could talk about the population of squirrels in our area or dogs or cats. Enlarging our view, next comes a community. An example of a community is the town or place we live. A more accurate biological description would include all the living things in that area. A community is composed of many species, including plants and animals An ecosystem not only considers the living things in an area, but also the physical environment and the interrelated flow of energy. You may live in a desert ecosystem, a forest ecosystem, or another kind of ecosystem. Most complex of all is the biosphere. In our case, this includes the all the areas of our planet where living things are...
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...Autoliv is a world class example of lean manufacturing. This Fortune 500 Company makes automotive safety components such as seat belt, airbags, and steering wheels, and has over 80 plants in more than 32 countries. Revenue in 2007 topped $6.7 billion. Autoliv’s lean manufacturing environment is called the Autoliv Production System (APS), and is based on the world’s largest automobile manufacturers, and embodied in its Toyota Production System (TPS). At the heart of Autoliv is a system that focuses on continuous improvement. Based on the “House of Toyota”, Autoliv Ogden, Utah, air bag plants put the concepts embodied in the house to work every day. The only difference between the Toyota house and the one at Autoliv is that the company has added a third pillar to its house to represent employee involvement while the norm in Japan not always found in the United States Autoliv started its journey back in 1995 at the time the ogden plant was manufacturing capacity with 22work cells company managers acknowledge that back then Autoliv was “broken” and in need of significant and immediate change if it was to survive. This meant that everyone from senior management to employees and suppliers needed to be on board with rebuilding the company. It was not that the company could not fulfill the needs of its automaker customers however with increasing demand for both reliable and cost effective component supplies pressure to change become obvious. Recognizing the value of Toyotas approach...
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...Name: Phoenix Bradley Course: COM/155 Tutor: Kimberly Parry Date: 9/22/13 Characterizing Zygomycosis and Whooping Cough Two Pathogens That Cause Infectious Diseases Infectious diseases are illnesses are highly transmissible and are caused by pathogens. The pathogens live and multiply in the body of the host and they cause damage to the cells and lead to various complications depending on their target organs. The most common types of pathogens include bacteria, protozoa, fungi and Viruses. The modes of action when the pathogens get into the host organism are similar. They first multiply then start destroying different tissues and cells in the host organism. They may release toxins that make the host environment conducive for their survival. The toxins harm the cells of the host organism, thus leading to different illnesses. The illnesses caused are normally very infectious, and they may lead to epidemics. This paper will compare and contrast the pathogens causing whooping cough and zygomycosis. Causal pathogens Whooping cough and Zygomycosis are some of the infectious diseases caused by different pathogens. In whooping cough, the pathogen infects the respiratory system, causing severe coughing in the victims. It is caused by the bacteria Bordetella pertussis. Zygomycosis is a broad range of fungal infectious diseases that affect the face; particularly the nasal cavity, and the eyes as well as the skin. It is caused by fungi...
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...9.4 Water Balance The body’s internal environment of extracellular fluid must maintain a constant volume, solute content, and often temperature. Humans and other organisms require a stable aqueous environment to survive. They carry this aqueous environment inside their body, and they must continuously replenish and maintain it. Aquatic organisms must also maintain their internal environment, since the conditions of the external environment change in terms of solutes and temperature. Atlantic salmon spends part of its life cycle in both freshwater and saltwater environments. For the first few years of its life, the salmon lives in freshwater rivers and lakes, where the solute concentration is less than the concentration within its body. This concentration gradient results in the uptake of water into the salmon’s internal environment, and therefore homeostatic mechanisms must expel the excess water from the body. As the salmon matures, it abandons the freshwater environment for the salt water of the Atlantic Ocean, where the concentration of solutes is higher. In this saltwater environment, the salmon experiences a continuous loss of water from its body, which it must replenish. Because water is not as abundant on land as it is in aquatic environments, terrestrial organisms require mechanisms to conserve water and maintain a homeostatic balance of solutes within their body. OSMOSIS – define the following: During osmosis, water molecules move from a region where they are highly...
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...of change that has transformed life on Earth DNA Deoxyribonucleic acid: a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix Biology The scientific study of life Emergent properties New properties that arise with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases. Systems Biology An approach to studying biology that aims to model the dynamic behavior of whole biological systems based on a study of the interactions among the system's parts. Eukaryotic Cell A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with eukaryotic cells (protists, plants, fungi, and animals) are called eukaryotes. Prokaryotic Cell A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with prokaryotic cells (bacteria and archaea) are called prokaryotes. Gene A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses). Biosphere The entire portion of Earth inhabited by life; the sum of all the planet's ecosystems. Ecosystems All the organisms in a given area as well as the abiotic factors with which they interact; one or more communities and the physical environment around them Community All the organisms that inhabit a particular area; an assemblage of populations of different species...
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...Cell Membrane Transport Harjot Dhesi Zoology 2011-13 Amon Gekombe 17 February 2014 Introduction The human body must maintain a balance within itself in order to abstain from disturbances caused by the external environment, for example a sudden increase in the outside temperature, or even the internal environment of the body, such as a dramatic drop in blood pressure. The body maintains this equilibrium through various methods and regulators, beginning in the cellular level. The human cell has a selectively permeable plasma membrane, allowing only certain substances to easily pass through to reach the inside or outside of the cell. Small, uncharged, and nonpolar molecules pass with the most ease through the plasma membrane (Tortora and Derrickson 2012). The constant moving in and out of substances is crucial in sustaining the life of the cell. Tortora and Derrickson explain in their book Principles of Anatomy and Physiology that, “Certain substances must move into the cell to support metabolic reactions. Other substances that have been produced by the cell for export or as cellular waste products must move out of the cell” (Tortora Derrickson 2012). Because of the selectively permeable nature of its plasma membrane, the cell can retain chemicals that have a difference in concentration on the inside than on outside of the cell. This is called the concentration gradient. A substance can either move against its concentration gradient by an active process, which requires...
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...Unit 1.3 Task 1a Cell membrane – The cell membrane is a biological membrane that’s job is to separate the interior of a cell from all of the cells in the outside environment. It is selectively permeable to ions and organic molecules. It also controls the movement of substances in and out of a cell. The function of the cell membrane is to protect the cell from its surroundings. The cell membrane can be found in plants and animal cells. Cell wall – The cell wall is a very flexible but tough layer that surrounds some types of cells. It can be found on the outside of a cell on the outer layer of the cell membrane. It provides cells with structural support and protection. The major function of the cell wall is to act as a pressure vessel. This prevents...
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