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2 min video on human population growth

This directed case study examines differences between the exponential and logistic growth models in biology and how they are applied to solve real life problems. The narrative follows a student returning to the United States as he tries to assess his possible exposure to Middle East Respiratory Syndrome (MERS). To better understand his risk, James needs to get up to speed on a variety of topics including the difference between infection, transmission, virulence, etc., and how these topics can be mathematically modeled not only in relation to MERS, but also with respect to Ebola and influenza. This case was designed for use in the second semester of a biocalculus course or a course involving ordinary differential equations, which are appropriate for second year undergraduate students majoring in biology, pre-med, and bio-mathematics. These students typically have completed a semester of calculus and one year of general biology. The case provides an opportunity for students to develop their understanding of differential equations and increase their appreciation of mathematics as it applies to solving a problem of biology.

Children with obese fathers have different epigenetic markings on the gene for insulin-type growth factor 2 (IGF2)-which is important during fetal growth and development-than children with fathers of normal weight.

Most colon cancers may be caused by infections with bacteria that are normally found in cows. For decades we have known that Streptococcus gallolyticus gallolyticus (SGG) is sometimes found in colon tumours, but now the microbes have been found to directly cause tumour growth in mice.

4 min video going over the idea backed by research that your brain really is like a muscle: the more you use it, the stronger it gets.

The following six lessons enable students to use different features of the site to explore trends in population, the environment, and human well-being over the past 2,000 years, as well as projections of future growth. The lessons are designed for high school science and social studies classrooms and address current national and state standards, as well as content for several Advanced Placement (AP) courses. Links to standards and AP course outlines are available in a searchable database.

A kind of salmon that's been genetically modified so that it grows faster may be on the way to a supermarket near you. The Food and Drug Administration approved the fish on Thursday - a decision that environmental and food-safety groups are vowing to fight. This new kind of fast-growing salmon was actually created 25 years ago by Massachusetts-based AquaBounty Technologies. A new gene was inserted into fertilized salmon eggs - it boosted production of a fish growth hormone. The result: a fish that grows twice as fast as its conventional, farm-raised counterpart.

What an incredible transformation. A protein used to help bones mend can also force pancreatic cells into producing insulin. The discovery could help people with type 1 diabetes produce their own insulin without having to take daily injections. In type 1 diabetes, beta cells in the pancreas that make insulin - the hormone that keeps our blood glucose levels at a safe concentration - are destroyed by the immune system. As a result, people with the disease have to inject themselves daily with insulin. Now, researchers have discovered that non-beta cells in the pancreas can be transformed into insulin-producing cells, merely by exposing them to a growth factor called BMP-7.

For the first time in modern history, the world's population is expected to virtually stop growing by the end of this century, due in large part to falling global fertility rates, according to a Pew Research Center analysis of new data from the United Nations. By 2100, the world's population is projected to reach approximately 10.9 billion, with annual growth of less than 0.1% - a steep decline from the current rate. Between 1950 and today, the world's population grew between 1% and 2% each year, with the number of people rising from 2.5 billion to more than 7.7 billion.

n this interrupted case study, students learn about the influence of early fetal nutritional conditions on the expression of genes related to metabolism and growth. Beginning with the true event of a food and fuel embargo that led to famine in the western Netherlands toward the end of World War II, students learn about the historical background of the Dutch Hunger Winter and its social impact. Using real data from the study conducted by Heijmans and coauthors (2008), students then compare the methylation level of a specific gene between individuals conceived during the famine and their unaffected siblings, and how changes in the expression of this metabolically important gene may impact the risk of developing type 2 diabetes. Supported by other studies on mice and in humans, students conclude that in utero events may impact the health of individuals later in life through epigenetic mechanisms. The case is ideally suited for a molecular or cell biology course, but is also appropriate for an introductory biology course in which students have an understanding of descriptive statistics, interpretation of statistical test results, eukaryotic gene structure, and regulation of gene expression.

In 1977, a University of Oxford statistician named Richard Peto pointed out a simple yet puzzling biological fact: We humans should have a lot more cancer than mice, but we don't. Dr. Peto's argument was beguilingly simple. Every time a cell divides, there's a small chance it will gain a mutation that speeds its growth. Cells that accumulate several of these mutations may become cancerous. The bigger an animal is, the more cells it has, and the longer an animal lives, the more times its cells divide. We humans undergo about 10,000 times as many cell divisions as mice - and thus should be far more likely to get cancer.

This 8-minute video is derived from the 2013 Holiday Lectures on Science. In it, Dr. Charles Sawyers explains the difference between proto-oncogenes, oncogenes, and tumor suppressor genes, and how mutations in these genes drive cancer development. "Cancer genes" can affect several cellular processes that he groups into three categories: cell growth and survival (i.e., genes involved in the cell cycle, cell fate (i.e., genes involved in cell differentiation), and genome maintenance (i.e, genes involved in DNA repair.)

A new compound, discovered jointly by international pharmaceutical company Servier, headquartered in France, and Vernalis (R&D), a company based in the UK, has been shown by researchers at the Walter and Eliza Hall Institute and Servier to block a protein that is essential for the sustained growth of up to a quarter of all cancers.

To understand the importance of elements to nutrition. Of the approximately 115 elements known, only the 19 highlighted in purple in Figure 1.26 are absolutely required in the human diet. These elements-called essential elements-are restricted to the first four rows of the periodic table (see Chapter 32 "Appendix H: Periodic Table of Elements"), with only two or three exceptions (molybdenum, iodine, and possibly tin in the fifth row). Some other elements are essential for specific organisms. For example, boron is required for the growth of certain plants, bromine is widely distributed in marine organisms, and tungsten is necessary for some microorganisms.

It is easy to miss something that is difficult to see and breast cancer tumour growth may go unnoticed. That is why knowing the early signs of breast cancer is key. For many, the first sign of breast cancer is a lump in the breast. However, breast cancer symptoms can vary widely - from lumps to some less obvious signs such as skin changes. Discovering a symptom of breast cancer does not necessarily mean it is cancer, however, it is absolutely vital to have a discussion with your doctor as soon as possible.

This directed case study follows two college roommates, Darrell and Anthony, who have just returned to school after winter vacation. They share that their ageing fathers are concerned about their declining faculties and are amused by their fathers' efforts to reverse the process.  Darrell's dad plays "brain games" on the computer while Anthony's father believes running will slow his memory decline. Intrigued, the roommates search through their biopsychology class notes to find out whether their fathers are correct. They review the topics of synaptic formation and plasticity, including axonal and dendritic development, and chemical factors in the brain that promote the survival and growth of neurons or stop the genetically programmed death of neurons. Based on research findings, students reading this case will decide whether Darrell and Anthony's fathers are correct in their assertions. The case is appropriate for a wide variety of courses including introductory anatomy or physiology, or for upper-division biopsychology, biology, or neuroscience courses.

For Collinge, this led to a worrying conclusion: that the plaques might have been transmitted, alongside the prions, in the injections of growth hormone-the first evidence that Alzheimer's could be transmitted from one person to another. If true, that could have far-reaching implications: the possibility that 'seeds' of the amyloid-β protein involved in Alzheimer's could be transferred during other procedures in which fluid or tissues from one person are introduced into another, such as blood transfusions, organ transplants and other common medical procedures.

Based on a comprehensive analysis of the scientific evidence, as required by the Federal Food, Drug and Cosmetic Act (FD&C Act), the FDA has determined that AquAdvantage Salmon meets the statutory requirements for safety and effectiveness under the FD&C Act. The salmon are safe to eat, the introduced DNA is safe for the fish itself, and the salmon meet the sponsor's claim about faster growth. Because the sponsor has met these requirements, the FDA must approve the application. The FDA has also analyzed the potential environmental impact that an approval of the AquAdvantage Salmon application would have on the quality of the human environment in the United States and has issued its final Environmental Assessment and Finding of No Significant Impact.

This interrupted case study introduces the topic of bacterial sporulation and cannibalism in Bacillus subtilis. The storyline follows Susan and her lab mates who are presenting research at a lab meeting when Susan falls asleep and dreams they are stranded on a deserted island. She makes connections between their fight for survival in the dream and the survival mechanisms of the bacteria they study in the lab. The benefits of sporulation under conditions of sustained stress are fairly obvious, but Susan's dream is used to examine the idea that sporulation may not always be beneficial and that bacteria would not want to commit to entering such a state in response to temporary stresses. Through the analysis of actual data from the scientific literature, students uncover a mechanism by which B. subtilis delays its commitment to sporulation by killing members of its own species to release nutrients (i.e., cannibalism). Originally developed for a general undergraduate microbiology course when discussing the structure and growth of prokaryotic cells, the case could also be used in an introductory biology course that emphasizes bacteria and data literacy.

This case study explores the controversy surrounding Yellowstone bison (Bison bison) and the relationship between wildlife management and pluralist democracy. In the late 1960s Yellowstone National Park suspended the policy of strictly managing bison by culling in favor of "natural processes" management. This led to dramatic herd growth and to bison exiting the park in winter in search of forage. Montana cattle ranchers reacted angrily for fear that the animals would infect their cattle with brucellosis. Since 2000, several government agencies have administered the Interagency Bison Management Plan, which uses culling to manage the population at around 3,000 head. The resumption of culling has upset environmental groups, while the recently approved expansion of bison habitat beyond park boundaries continues to upset ranchers.  The ongoing political battle between ranchers, environmentalists, Native American tribes and government agencies shows how difficult it can be to balance legislative mandates, ecological values, and conflicting public demands. The case study may be employed in a variety of courses, including American Government, Public Policy, Interest Groups, Environmental Studies and National Parks.