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Stem Cell Overview Article with embedded Video 7:53 Discusses gene expression/differentiation 2 minute segments -Pluripotent stem cells in early embryo CDX2 OCT3/4, Inner cell mass start- 1:50 - Characteristics of Stem Cells: differentiation, abilities of stem cells,  1:55- 3:17 - Stem Cells in the Adult Body: red blood cell hematopoetic stem cells, differentiation, small intestine crypts,  3:20-5:35 - Embryonic Stem Cells in Culture: ES pluripotent cells ES cells, treat to neural lineages, culture conditions, study differentiate into lineages 5:40- 7:53

How do cells in your body differentiate into other types of cells? Explore cell specialization featuring stem cells and the role they play in cell differentiation.

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.

This case study challenges students to differentiate between anecdotal evidence and science-based evidence related to human health. The case uses a "flipped" approach in which students watch two preparatory videos prior to attending class. The first video defines anecdotal evidence while the second characterizes the different categories of scientific studies that generate evidence that is not anecdotal. Students watch the videos, analyze scenarios for anecdotal evidence, and think about what types of evidence they use to make health-related decisions. When students meet in class, they work in groups to compare and contrast these different categories of scientific studies and classify actual research studies aided by a dichotomous key for distinguishing between different types of studies related to human health. Primarily designed for students in introductory general biology courses, the activity could also be useful for lower division nutrition, physiology, or non-major biology courses or any course where students need to differentiate between science and pseudoscience.

" IBM scientists have been able to differentiate the chemical bonds in individual molecules for the first time using a technique known as noncontact atomic force microscopy (AFM)."

1:30 animation As a human embryo develops, its cells become progressively restricted in the types of specialized cells that they can produce. Inner cell mass (ICM) cells of the blastocyst can make any type of body cell. Gastrula-stage cells can give rise to the cells of a given germ layer. Later, cells become even more restricted. For example, the pancreatic bud of the endoderm layer can only make the cells of the pancreas.

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.)

This interrupted case study, designed for an introductory biology or environmental science course, introduces students to the complexity of ecosystems by examining changes in trophic interactions and abiotic factors in a freshwater ecosystem as a result of human actions. The case narrative describes the recent and undesirable appearance of decomposing algae (Cladophora glomerata) on a public beach in the Laurentian Great Lakes. Students are asked to use the scientific method by creating hypotheses and examining observational data to describe biotic and abiotic components of the Great Lakes ecosystem. The case requires students to differentiate between benthic and pelagic environments (e.g., the influence of depth and phytoplankton density on light availability, and the availability of phosphorus) and the interactions between organisms in both environments. Students also examine shifts in these interactions as a result of the newly introduced zebra and quagga mussels, which have ultimately resulted in the algae's presence on the beach. There are also opportunities to discuss the impact of these ecosystem changes on people who own property and/or visit the beach.

Possibly the most exciting use of stem cells rests on their ability to differentiate into an enormous range of healthy functioning adult cells, thereby providing a replacement source of cells to treat serious diseases. This ultimately means that virtually any disease that results in cellular and tissue destruction can potentially be treated by stem cells. Some of the conditions are particularly debilitating and these include diabetes, spinal cord injuries, retinal disease, Parkinson's disease, heart disease and cancer.

Normally, male squirrel monkeys can't distinguish between red and green hues-they're what is called color-blind in humans. The South American Saimiri genus lacks a gene that allows color-sensitive cells in the eye, called cones, to differentiate red and green from gray. To these animals, other colors, such as blue, brown and orange, appear faded. But Sam was one of two males in the experimental group of a groundbreaking 2009 ophthalmological study conducted at the Washington National Primate Research Center in Seattle. Husband-and-wife vision researchers Jay and Maureen Neitz injected a viral vector behind the retinas, the part of the eye that responds to color, of Sam and his simian lab partner, Dalton. The virus contained the genetic code in human eyes for red pigment, giving the monkeys an extra class of cone photoreceptor.

When you look at yourself in the mirror you may ask, 'How, given that all the cells in my body carry the same DNA, can my organs look so unlike and function so differently?' With the recent progress in epigenetics, we are beginning to understand. We now know that cells use their genetic material in different ways: genes are switched on and off, resulting in the astonishing level of differentiation within our bodies.

Information is easily accessible for teachers, administrators, parents and students. Standards-based units, lesson plans, instructional guides and project based learning designs model the integration of content, learning skills and technology standards, research-based instructional strategies, differentiated instruction and rich classroom assessments, including a culminating performance, product or project with an accompanying rubric.

Existing mouse models of lethal Ebola virus infection do not reproduce hallmark symptoms of Ebola hemorrhagic fever, neither delayed blood coagulation and disseminated intravascular coagulation, nor death from shock, thus restricting pathogenesis studies to non-human primates. Here we show that mice from the Collaborative Cross exhibit distinct disease phenotypes following mouse-adapted Ebola virus infection. Phenotypes range from complete resistance to lethal disease to severe hemorrhagic fever characterized by prolonged coagulation times and 100% mortality. Inflammatory signaling was associated with vascular permeability and endothelial activation, and resistance to lethal infection arose by induction of lymphocyte differentiation and cellular adhesion, likely mediated by the susceptibility allele Tek. These data indicate that genetic background determines susceptibility to Ebola hemorrhagic fever.

 is a web-based library of inquiry-based character-driven animated mysteries paired with differentiated supplemental activities that exposes students to the thrill of problem-solving. Mosa Mack allows educators to engage students while teaching standards-aligned content in a fun and engaging way while modeling scientific processing skills. Through its female protagonist whose passion for problem solving drives each story, Mosa Mack promotes diversity in the sciences while simultaneously providing teachers with an accessible way to incorporate inquiry into the classroom. Mosa Mack's unique inquiry-based approach targets the development of critical thinking skills for all students, with a particular focus on girls and minorities with historically low participation STEM fields.

This PowerPoint-driven, flipped case study begins with a short video about a woman suffering from cystic fibrosis (CF) in the 1970s, a friend of the lead author's, whom she met in college and who died in her twenties. Hooked by this personal story, students then delve into the genetics and biology of cystic fibrosis as they learn about the difference between dominant and recessive genes, make Punnett squares that depict various types of inheritance, distinguish between probability and actual numbers, differentiate types of mutations, and learn about the opportunistic infections that CF patients often succumb to.  Students conclude the case by watching two additional videos on chest compression machines and the contemporary life expectancy of patients with CF.  In addition to the scientific content presented in the case, it is hoped that students will empathize with, and be motivated by, the young people presented in the videos as they struggle with a very real, incurable disease deeply rooted in genetics.

This case study describes a visit by "Naomi" to her physician, who upon seeing Naomi's bloodwork decides to prescribe her a cholesterol-lowering agent, a statin. The case discusses (1) the prevalence of non-communicable diseases such as atherosclerosis, which can lead to strokes and heart disease; (2) circulating lipoprotein particles including LDL and HDL, differentiating between which is a risk factor for heart disease and which is protective;  (3) the pathway for cholesterol synthesis; (4) the evidence demonstrating that statins inhibit the enzyme HMG-CoA reductase, which is the committed step for cholesterol synthesis; and (5) the kinetic mechanism by which statins inhibit the enzyme. Students examine and interpret data from radioactive tracer and enzyme kinetics studies. The case ends with another visit by Naomi to her physician, who reexamines her bloodwork after she has been taking a statin for six months. Students are asked to determine whether the drug was effective for Naomi and, if not, what changes could be made to her regimen. The case was originally written for use in a survey of biochemistry course for upper level undergraduates.

Although rabies still causes thousands of deaths globally every year, it has essentially been eradicated from most industrialized countries. Part of the success story is due to an unusual project undertaken by the Swiss prompted by a series of large outbreaks in the 1970s: the large-scale vaccination of wild foxes to stop the epidemic. In this directed case study, students use an easily accessible MS Excel-based model to understand key epidemiological parameters of rabies outbreaks in wild foxes. The simple model allows students also to predict what proportion of foxes needs to be vaccinated to eradicate the virus from the population. The case fits into both ecological and microbiological (epidemiological) courses and offers opportunities to explore zoonotic diseases and "One Health" questions. The mathematical basis of the differential equations in the models is explained, although prior knowledge of calculus is not essential. A key learning outcome is the critical understanding of both the power and limitations of simple epidemiological models. This case was written for an online course but could also be used as a face-to-face activity if students have access to computers in class.

groups of cells in the blastula are synchronized to divide at the same time through mitosis. Some of these cells will eventually give rise to the sand dollar's germ cells. Others will play important roles in various developmental processes, such as cell differentiation, the formation of the digestive system, and the development of the exoskeleton. Despite their different characteristics and roles, all of the sand dollar's cells (except for eggs or sperm) are genetically identical due to mitosis.

Explore some examples of specialized plant and animal cells with the Amoeba Sisters! This video explains how specialized cell structure suits their function.