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Text and interactives on human evolution and genetic structure

Data Analysis from The Cornell Lab-Basics of Science Pipes By Yoomee Kim, Lisa Adler-Golden, and Andrea McMillen (ESA) Science pipes works by clicking and dragging the data, operations, and desired output boxes to the workspace. You create a pipeline by drawing lines between the boxes.  Activities include: Cemetery Demography, Darwin's Finches, Forest Population Structure and North American Pollen

7:37 video Join us as we explain virus structure, the lytic cycle, and the lysogenic cycle! Music Credit: Adrian Holovaty, OverClocked ReMix (http://ocremix.org) Teachers, we have a handout that matches this video available for free on our website: http://www.amoebasisters.weebly.com/h...

Shape of Life is a series of FREE short classroom videos that beautifully illustrate the evolution of the animal kingdom on planet earth. Based upon an original PBS Series, Shape of Life is especially designed for students and teachers who want a first-hand account of how animals adapt and thrive. The series is NGSS aligned with exquisite focus on diversity, biodiversity, adaptability, body structure, design, behaviors, and the innovative scientists who explore these creatures.

Shape of Life is a series of FREE short classroom videos that beautifully illustrate the evolution of the animal kingdom on planet earth. Based upon an original PBS Series, Shape of Life is especially designed for students and teachers who want a first-hand account of how animals adapt and thrive. The series is NGSS aligned with exquisite focus on diversity, biodiversity, adaptability, body structure, design, behaviors, and the innovative scientists who explore these creatures.

Rosalind Franklin was a British scientist who helped discover the structure of DNA, but you most likely haven't heard of her. Hank will attempt to fix this gap in your knowledge on today's SciShow: Great Minds.

DNA has a double helix structure. If untwisted, DNA looks like two parallel strands. Each strand has a linear sequence of A, C, G, and T. The precise order of the letters carries the coded instructions. One strand is a complementary image of the other: A always pairs with T, and C always pairs with G.

In 1950, Erwin Chargaff published a paper stating that in the DNA of any given species, the ratio of adenine to thymine is equal, as is the ratio of cytosine to guanine. This became known as Chargaff's ratio, and it was an important clue for solving the structure of DNA.

When it's completely unraveled, DNA is known to extend approximately six feet in length, yet is somehow able to cram itself into a cell's nucleus. In a study published today (July 27) in Science, researchers created a novel visualization method that revealed a 3-D glimpse of chromatin as it sits jam-packed within the nuclei of human cells. The researchers found that, contrary to how it's depicted in most textbooks, chromatin does not fold in on itself in an organized manner to create distinct structures. Instead, it forms a pliable, inconsistent chain characterized by a wide variety of folding patterns. 

The discovery of the structure of DNA was one of the most important scientific achievements in human history. The now-famous double helix is almost synonymous with Watson and Crick, two of the scientists who won the Nobel prize for figuring it out. But there's another name you may not know: Rosalind Franklin. Cláudio L. Guerra shares the true story of the woman behind the helix.

Researchers have pinpointed a catalytic trigger for the onset of Alzheimer's disease - when the fundamental structure of a protein molecule changes to cause a chain reaction that leads to the death of neurons in the brain.

One of the most important molecules relating to cancer is called p53. This Click and Learn explains the structure and function of the p53 protein as well as how the protein's activity is regulated. Learn why p53 is called the guardian of the genome and how interfering with its function can lead to cancer.

Buckle up for a prokaryote and eukaryote comparison before taking a ride into a cell to explore organelle structures and functions! This cell introduction also includes the modern cell theory.

Humans construct boundaries -- around our homes, our neighborhoods, and our nations -- to bring order to a chaotic world. But we rarely consider how these boundaries affect other creatures. In this episode of Think Like A Scientist, we meet conservation photographer Krista Schlyer, who has spent the last seven years documenting the environmental effects of the U.S./Mexico border wall, and biologist Jon Beckmann, who studies how man-made barriers influence the movement of wildlife. Schlyer and Beckmann have seen damaging impacts of the border wall firsthand, but they remain optimistic. Humans probably won't stop constructing walls and fences any time soon, but planning our boundaries with wildlife in mind can help prevent these structures from causing environmental harm.

In this video Paul Andersen explains how the chloroplast in plants harnesses power from the Sun to form high energy molecules like glucose. The structure of a chloroplast as well as a brief discussion of the light reaction and Calvin cycle are included.

In order to improve the surgical outcome of these procedures and enhance patient quality of life, new and better tools are needed for esophageal reconstruction. Biostage is working on a new regenerative technology to address esophageal cancer through their pioneer Cellframe Technology. Two weeks before the surgery, stem cells are harvested from patient abdominal adipose tissue and allowed to incubate with a biocompatible esophageal implant. These cells interact and adhere to the implant and are able to respond to signals for regeneration once inside the patient, potentially restoring both the structural and functional integrity of the esophagus. These new approaches to organ implants could revolutionize resectional surgery by providing patients with functional replacements derived from their own cells.

This case study was developed for an introductory biology course with the goal of integrating content (specifically, structure/function, signaling pathways, and homeostasis) while reinforcing general critical thinking skills and the scientific method (generating hypotheses, evaluating evidence, and making predictions). The case is suitable for a flipped classroom and there are several videos associated with it. The case revolves around an obese two-and-a-half-year-old boy who won't stop eating. Students become familiar with some basic concepts related to obesity and leptin signaling through the videos that they watch before class. They then use class time to work through the case (delivered as an interactive slide show, including several clicker questions) to determine the genetic basis for this child's obesity and possible therapies to manage his weight. The case could also be adapted and expanded to be used in a physiology course to explore the interaction of various hormones that regulate appetite and metabolic rate or in a cell biology class to explore JAK-STAT signaling.

Although Hardy-Weinberg equilibrium is a fundamental part of introductory biology classes, students often have difficulty understanding its implications. This interrupted case study places students in the role of small teams who are conducting preliminary research into the impact of roads on the population structure of timber rattlesnakes in order to apply for a grant for further research. Research groups consisting of 3-4 students work through a series of questions allowing them to use HWE principles to discover for themselves how deviations from HWE can have implications for conservation biology. Periodic interruptions with help sheets (see Supplemental Materials) allow teachers to maintain an active role in the students' progress, while also demonstrating the collaborative nature of scientific research. Ultimately students formulate formal emails summarizing and interpreting their findings in order to "apply" for the grant. The case is designed for undergraduate students in introductory biology or in lower-level population genetics/conservation courses where connecting basic genetic principles to ecology and sustainability is key.

It's one of the big mysteries of cell biology. Why do mitochondria-the oval-shaped structures that power our cells-have their own DNA, and why have they kept it when the cell itself has plenty of its own genetic material? A new study may have found an answer. Scientists think that mitochondria were once independent single-celled organisms until, more than a billion years ago, they were swallowed by larger cells. Instead of being digested, they settled down and developed a mutually beneficial relationship developed with their hosts that eventually enabled the rise of more complex life, like today's plants and animals.

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 was inspired by a real-life scenario, and follows the story of Roberto, a migrant farmworker whose health is impacted by the usage of pesticides on a farm.  With the help of a health care provider, Roberto becomes aware of the effects of pesticides on his well-being. Students utilize a database and draw conclusions from data in order to answer the case questions.  The case concludes with an activity that uses the "intimate debate" technique in which students use scientific data as evidence to argue whether or not the pesticide under discussion should be banned from usage.  This case was originally developed for undergraduate anatomy and physiology or toxicology courses. Students are expected to have some background knowledge in nerve structure and function as well as the mechanics of neural transmission before starting the case.