Group items tagged

A paper published today in Science Advances just might change that. By creating a reliable method of studying viruses' long evolutionary history-hitherto nearly impossible-researchers have found new evidence that strongly suggests viruses are indeed living entities.

" The typical naked mole rat lives 25 to 30 years, during which it shows little decline in activity, bone health, reproductive capacity and cognitive ability. What is the secret to this East African rodent's long, healthy life?"

online NY regents Living Environment Test Prep site

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 animated short film tells the engaging tale of the discovery of the coelacanth. In 1938, South African museum curator Marjorie Courtenay-Latimer came across a strange blue fin poking out of a pile of fish. With its fleshy, lobed fins and its tough armored scales, the coelacanth did not look like any other fish that exists today. The coelacanth belongs to a lineage that has remained virtually unchanged for hundreds of millions of years-earning it the description of a "living fossil."

no idea where to draw the line between living and dead things. Which leads to mind-blowing implications. What is life after all? And is death really a thing? Lets look into it together

In this tutorial you will be learning about the Linnaean system of classification used in the biological sciences to describe and categorize all living things.  The focus is on finding out how humans fit within this system.  In addition, you will discover part of the great diversity of life forms and come to understand why some animals are considered to be close to us in their evolutionary history.

In this interrupted case study, students will help Dr. Gupta investigate and assess complications arising in one of her long-term patients, Jorge Alvarez. Jorge was diagnosed with Type II diabetes mellitus 10 years ago as documented in "Living the Sweet Life," an optional prequel case study also in the NCCSTS collection. Jorge has been working with Dr. Gupta to manage his condition, but this year he has come under additional stress, both emotionally and financially, and his health has deteriorated. Jorge now presents with several new signs and symptoms, including numbness, tingling and burning sensations, and a foot sore that just won't heal. Students will review the nervous system and assess Jorge's symptoms, vitals, and blood tests to determine if his diabetes has worsened. Students will also learn about tests used to diagnose types of neuropathy and consider which of them would be most beneficial for Jorge. In addition to a non-majors anatomy and physiology course, this case study may be appropriate for an introductory biology, nutrition/dietetics, or a sensory and perception course.

"Biologists at the University of Rochester have determined how blind mole rats fight off cancer -- and the mechanism differs from what they discovered three years ago in another long-lived and cancer-resistant mole rat species, the naked mole rat."

What happens if you get a blood transfusion with the wrong blood type? Even though a patient's own blood type is the first choice for blood transfusions, it's not always available at the blood bank. Try to save some patients' lives and learn about human blood types!

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.

Sure, we know insufficient serotonin levels get a bad rap when it comes to depression, but that's like blaming one person in a full-scale riot. Depression isn't caused by only one factor. In fact, study co-author Elyse Aurbach says we're probably not getting to the core of why people are depressed because "the brain is immensely complex." In this study, the research team conducted eight experiments (four on animal brains, four on brains of the deceased human kind) of varying sample sizes - from 20 to 90 brains in each - and found that the brains of deceased humans who'd been depressed had increased levels of hippocampal FGF9 and that live animals with increased FGF9 levels demonstrated depressive, anxious behavior. "This is not just a correlation," study leader Huda Akil of the University of Michigan says. Less really may be more, at least when it comes to FGF9.

A team of scientists unveiled a new tree of life on Monday, a diagram outlining the evolution of all living things. The researchers found that bacteria make up most of life's branches. And they found that much of that diversity has been waiting in plain sight to be discovered, dwelling in river mud and meadow soils.

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.

Because the gene-enzyme system forms a closed loop, it presents us with a classic chicken or egg conundrum: Which came first, genes or the protein enzymes they code for? While the details are still not fully worked out, discoveries over the past few decades have lead researchers to a surprising possible solution: What really came first? Genes that act as enzymes! The RNA World Hypothesis is the idea that before living cells, the genetic code, and the gene/protein cycle ever existed, chains of a chemical called RNA were forming naturally. Once formed, some of these chains were able to function as enzymes, and were even able to evolve by making copies of themselves with slight, accidental modifications.

Humans may in part owe their big brains to a DNA "typo" in their genetic code, research suggests. The mutation was also present in our evolutionary "cousins" - the Neanderthals and Denisovans. However, it is not found in humans' closest living relatives, the chimpanzees. As early humans evolved, they developed larger and more complex brains, which can process and store a lot of information. Last year, scientists pinpointed a human gene that they think was behind the expansion of a key brain region known as the neocortex.

A deadly disease known as African sleeping sickness has puzzled doctors for decades. It would disappear from villages without a trace, only to re-emerge weeks or months later with no known cause. Frustrated health officials wondered how sleeping sickness could persist when not a single villager or animal-the disease's only carriers-tested positive for the insect-borne parasite that causes it. Now, scientists may have an answer at last: They've discovered the disease was hiding in plain sight this whole time, living in and even transmitting via human skin.

Chemist Daniel Nocera of Harvard University and his team joined forces with synthetic biologist Pamela Silver of Harvard Medical School and her team to craft a kind of living battery, which they call a bionic leaf for its melding of biology and technology. The device uses solar electricity from a photovoltaic panel to power the chemistry that splits water into oxygen and hydrogen.

Deadly bacteria are spreading through the oceans as waters warm up, and are increasing infection risks, according to a new study. Multiple species of rod-shaped Vibrio bacteria live in the world's oceans, and their populations rise and fall based on many different variables, changing the likelihood of making people sick.

A new study, published on Wednesday in Molecular Biology and Evolution, identifies gene variants in Inuit who live in Greenland, which may help them adapt to the cold by promoting heat-generating body fat. These variants possibly originated in the Denisovans, a group of archaic humans who, along with Neanderthals, diverged from modern humans about half a million years ago.