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PBS created a three-part television series based off of Neil Shubin's best-selling book, Your Inner Fish. Along with the series, they have created an excellent website with teaching resources, video clips, and interactive features to guide you through the record of evolution in our bodies.

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. 

Our students will face decisions about health, science, and medicine that we can hardly imagine.   How can we keep student needs and science first, yet still create a safe and affirming space for intellectual curiosity? Teaching biology creates many opportunities to authentically incorporate student curiosity. The Next-Generation Science Standards (NGSS) expect students to ask questions about natural phenomena and then explain their answers using models. This website offers examples of adapting curriculum to NGSS and gender-inclusive standards, as well as resources for advocating to administration and others.

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Meiosis, the form of cell division unique to egg and sperm production, sets the stage for sex determination by creating sperm that carry either an X or a Y sex chromosome. But what is it about the X or Y that determines sex? Before a meiotic cell divides, its two sets of chromosomes come together and cross over, or swap, segments. The first animation shows normal crossing over, where the X and Y chromosomes exchange pieces only at their tips. The second animation shows a rare mistake in which the Y chromosome transfers a gene called SRY to the X chromosome, resulting in sex-reversed babies. Studies of sex-reversed individuals led researchers to identify the master switch for sex determination, the SRY gene, which tells a fetus to become a boy.

Meiosis, the form of cell division unique to egg and sperm production, sets the stage for sex determination by creating sperm that carry either an X or a Y sex chromosome. But what is it about the X or Y that determines sex? Before a meiotic cell divides, its two sets of chromosomes come together and cross over, or swap, segments. The first animation shows normal crossing over, where the X and Y chromosomes exchange pieces only at their tips. The second animation shows a rare mistake in which the Y chromosome transfers a gene called SRY to the X chromosome, resulting in sex-reversed babies. Studies of sex-reversed individuals led researchers to identify the master switch for sex determination, the SRY gene, which tells a fetus to become a boy.

Scientists announced Monday that they had created mice with small amounts of human brain cells in an effort to make realistic models of neurological disorders such as Parkinson's disease.

Biologists at the Massachusetts Institute of Technology have created a genetically modified version of a common bacteria found in the gut that can sense the environment there and fight disease. And when this designer bacteria works, the proof is in the poop - glowing poop. (In this case, mouse poop.)

Scientists have created an "artificial womb" in the hopes of someday using the device to save babies born extremely prematurely. So far the device has only been tested on fetal lambs. A study published Tuesday involving eight animals found the device appears effective at enabling very premature fetuses to develop normally for about a month.

TeachEngineering.org is a collaborative project between faculty, students and teachers associated with five universities and the American Society for Engineering Education, with NSF National Science Digital Library funding. TeachEngineering.org is a searchable, web-based digital library collection populated with standards-based engineering curricula for use by K-12 teachers and engineering faculty to make applied science and math (engineering) come alive in K-12 settings. The TeachEngineering collection provides educators with *free* access to a growing curricular resource of multi-week units, lessons, activities and living labs. Initiated by the merging of K-12 engineering curricula created by four universities, the collection continues to grow and evolve over time with new additions from other universities, and input from teachers who use the curricula in their classrooms.

University of Washington Institute for Science and Mathematics Education has created partnerships to envision, cultivate, and study equity-focused educational models and practices in areas of science, technology, engineering, and mathematics (STEM). We do this work across the K-12 grade span and across formal and informal learning environments. We believe that all young people should be able to decide their own futures. Their opportunity to learn in STEM fields plays a critical role in their opportunity to do so now and in the future. We develop innovative projects that seek to deliver on this goal and closely study them to develop knowledge about how to broaden participation in STEM. The Institute is strongly affiliated with the Learning in Informal and Formal Environments (LIFE) Center.

As weather warms up off the coast of France, blooms of plankton have once again begun to form, creating a beautiful, multicolored swirl visible from space.

Most 12-year-olds love playing videogames -- Thomas Suarez taught himself how to create them. After developing iPhone apps like "Bustin Jeiber," a whack-a-mole game, he is now using his skills to help other kids become developers. (Filmed at TEDxManhattanBeach.)

A handful of scientists around the United States are trying to do something that some people find disturbing: make embryos that are part human, part animal. The researchers hope these embryos, known as chimeras, could eventually help save the lives of people with a wide range of diseases.

Such descriptions of GMOs raises fears about whether gene transfer between species is outside of how evolution operates and therefore unnatural. Research, however, has repeatedly shown the opposite to be true. In May 2015, researchers showed that practically every known species of cassava (sweet potato) contained genes from Agrobacterium, a bacterial species whose genes we have also harnessed to create other GM crops. The genes were inserted over 8,000 years ago and may have helped the tuber evolve into its current, edible form. This phenomenon of genetic transfer during evolution between species, also known as 'horizontal gene transfer' is not restricted to plants.

The sun shines a massive amount of energy onto the Earth's surface every day. What if humans could take a cue from plants and use sunlight to make their own food? From chloroplasts to carbon dioxide, Reactions creates a hypothetical photosynthetic human and gives a quick crash course on the chemistry of photosynthesis.

Geneticist Jennifer Doudna co-invented a groundbreaking new technology for editing genes, called CRISPR-Cas9. The tool allows scientists to make precise edits to DNA strands, which could lead to treatments for genetic diseases … but could also be used to create so-called "designer babies." Doudna reviews how CRISPR-Cas9 works - and asks the scientific community to pause and discuss the ethics of this new tool.

In this video Paul Andersen explains how the electrochemical gradient is a combination of the chemical and electrical gradient of ions. As ions move across a membrane the potential change creates a hidden force that isn't always apparent.

In this video Paul Andersen details the action potential in neurons. The resting potential of a neuron (-70mV) is maintained through differences in concentration and permeability of Na, K, and Cl ions. A graded potential is created as neurotransmitters from adjacent cells that are either excitatory or inhibitory. If the neuron reaches the threshold of -55mV an opening of voltage-gated sodium channels triggers an action potential

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.

The news that researchers want to create human-animal chimeras has generated controversy recently, and may conjure up ideas about Frankenstein-ish experiments. But chimeras aren't always man-made-and there are a number of examples of human chimeras that already exist. A chimera is essentially a single organism that's made up of cells from two or more "individuals"-that is, it contains two sets of DNA, with the code to make two separate organisms.