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Human activities currently add about nine gigatons of carbon to the atmosphere yearly. Photosynthetic organisms on land and in the ocean absorb about five of those gigatons through the natural uptake of CO2, leaving to humans the task of dealing with the rest. But no matter how much carbon there is, capturing it and preventing it from reentering the atmosphere is an immense engineering challenge; even today's best technology is orders of magnitude less effective than photosynthesis at trapping atmospheric carbon.

Scientists in Australia have grown the world's first kidney from stem cells - a tiny organ which could eventually help to reduce the wait for transplants. The breakthrough, published in the journal Nature Cell Biology, followed years of research and involved the transformation of human skin cells into an organoid - a functioning "mini-kidney" with a width of only a few millimetres.

4:30 video When life emerged on Earth about 4 billion years ago, the earliest microbes had a set of basic genes that succeeded in keeping them alive. In the age of humans and other large organisms, there are a lot more genes to go around. Where did all of those new genes come from? Carl Zimmer examines the mutation and multiplication of genes.

Quick look: In its modern sense, epigenetics is the term used to describe inheritance by mechanisms other than through the DNA sequence of genes. It can apply to characteristics passed from a cell to its daughter cells in cell division and to traits of a whole organism. It works through chemical tags added to chromosomes that in effect switch genes on or off.

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.

The groundwater is cold, deep and twice as salty as seawater, but the water streaming out of Blood Falls, which teems with microbes, tells us that it is unlikely to be lifeless. "The fact that the [water] contains metabolically active micro-organisms that appear to be suited to life in a dark, cold brine supports the idea that life should persist throughout the subsurface," says Mikucki. If so, those microbes could be fuelling life in the Southern Ocean. By breaking down iron-containing rocks they might be dumping as much as 170 million kilograms of iron into the ocean each year, according to the researchers' estimates, helping to explain why marine productivity is seasonally very high near to the coast.

The Genome Institute (TGI) is a world leader in the fast-paced, constantly changing field of genomics. A truly unique institution, we are pushing the limits of academic research by creating, testing, and implementing new approaches to the study of biology with the goal of understanding human health and disease, as well as evolution and the biology of other organisms.

Every year, it inflicts between 250,000 and 500,000 helpless and malnourished young people with early-life blindness. And in half of those cases, it also brings death, according to the World Health Organization. Vitamin A deficiency also puts pregnant women at risk. It's rare in developed countries, but the goal of completely eradicating vitamin A deficiency - mostly in Africa and Southeast Asia - remains unmet. Scientists are now working to genetically engineer "super" bananas that are fortified with crucial alpha- and beta-carotene, which the body converts to vitamin A.

An environmentally dependent method to excise particular genes and eliminate genetically modified organisms (GMOs) if they leave the lab, published this week (May 19) in Nature Communications, uses an inducible CRISPR/Cas9 genome-editing system to snip out vital pieces of the E. coli genome.

Collection of interactives for organs, skeleton, puberty, muscles, and the nervous system

This page shows some key events of human development during the embryonic period of the first eight weeks (weeks 1 - 8) following fertilization. This period is also considered the organogenic period, when most organs within the embryo have begun to form. There are links to more detailed descriptions which can be viewed in a week by week format, by the Carnegie stages or integrated into a Timeline of human development. Online resources available include: individual images of all Carnegie stages, scanning electron micrographs of the earlier stages, cross-sections showing internal structures at mid- and late-embryonic, 3D reconstructions of internal structures, animations of processes, ultrasound scans and information about abnormalites of development.

This list provides a range of valuable resources including guidelines, organization sites, toolkits, and information for public health professionals. If you are looking for training on a specific topic, please visit CDC TRAIN.

In molecular biology, ligation refers to the joining of two DNA fragments through the formation of a phosphodiester bond. An enzyme known as a ligase catalyzes the ligation reaction. In the cell, ligases repair single and double strand breaks that occur during DNA replication. In the laboratory, DNA ligase is used during molecular cloning to join DNA fragments of inserts with vectors - carrier DNA molecules that will replicate target fragments in host organisms.

The scientific progress that has made it possible to dream of a future in which faulty organs could be regrown from stem cells also holds potential as an ethical and greener source for meat. So say scientists who suggest that every town or village could one day have its very own small-scale, cultured meat factory.

Transgenic organisms, which contain DNA that is inserted experimentally, are used to study many biological processes. In this lab, you will create a transgenic fly to study circadian rhythms.

EPA is working with many other organizations to collect and communicate data about climate change. With help from these partners, EPA has compiled the third edition of this report, presenting 30 indicators to help readers understand observed long-term trends related to the causes and effects of climate change. In a manner accessible to all audiences, the report describes the significance of these trends and their possible consequences for people, the environment, and society.

In a paper this week in Science, Vogelstein and Cristian Tomasetti, who joined the biostatistics department at Hopkins in 2013, put forth a mathematical formula to explain the genesis of cancer. Here's how it works: Take the number of cells in an organ, identify what percentage of them are long-lived stem cells, and determine how many times the stem cells divide. With every division, there's a risk of a cancer-causing mutation in a daughter cell. Thus, Tomasetti and Vogelstein reasoned, the tissues that host the greatest number of stem cell divisions are those most vulnerable to cancer. When Tomasetti crunched the numbers and compared them with actual cancer statistics, he concluded that this theory explained two-thirds of all cancers.

4:17 video Think of the ozone layer as Earth's sunglasses, protecting life on the surface from the harmful glare of the sun's strongest ultraviolet rays, which can cause skin cancer and other maladies. Ozone stinks. People who breathe it gag as their lungs burn. The EPA classifies ground-level ozone as air pollution. Yet without it, life on Earth would be impossible. A fragile layer of ozone 25 km above Earth's surface is all that stands between us and some of the harshest UV rays from the sun. The ozone molecule O3 blocks radiation which would otherwise burn skin and cause cancer. On Mars, which has no ozone layer to protect it, solar UV rays strafe the surface with deadly effect, leaving the apparently lifeless planet without the simplest of organic molecules in the upper millimeters of exposed Martian soil.

You're probably aware of eight basic blood types: A, AB, B and O, each of which can be "positive" or "negative." They're the most important, because a patient who receives ABO +/- incompatible blood very often experiences a dangerous immune reaction. For the sake of simplicity, these are the types that organizations like the Red Cross usually talk about. But this system turns out to be a big oversimplification. Each of these eight types of blood can be subdivided into many distinct varieties. There are millions in all, each classified according to the little markers called antigens that coat the surface of red blood cells.

3 min Over billions of years, Earth has developed essential properties that allowed living organisms to form.