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Tag: "primitive" at biology news

Ancient retrovirus sheds light on modern pandemic

...ments with their primate cousins. Such vestiges of primitive infection, rendered inactive by eons of genetic mutation, make up about 8 percent of the human genome. Innate protection against PtERV1 in humans could be credited, the researchers believe, to the presence of an ancient, rapidly evolving antiviral ...

Puzzling plankton yield secrets to role in evolution/global photosynthesis

...plankton from the genus Ostreococcus emerge at the primitive root of the green plant lineage, dating back nearly 1.5 billion years. Today, these microscopic, free-living creatures, among the smallest eukaryotes ever characterized, barely a micron in diameter, contribute to a significant share of the world’s t...

Researchers publish first marsupial genome sequence

...hallenging the notion that marsupials possess only primitive immune systems. The opossum genome has an unusual structure with fewer chromosomes than the human genome (9 pairs versus 23 pairs, respectively) but a longer total length (3.4 billion versus 3 billion bases, respectively). ...

Study of protein folds offers insight into metabolic evolution

...benefited the formation of building blocks for the primitive RNA world, it makes a lot of sense that we've found this origin encased in nucleotide metabolism." ...

Paper challenges 1491 Amazonian population theories

...Meggers at Smithsonian (she argues these were very primitive people with low population). Mark's studies are the first to apply core sampling methodology to determine through coal and pollen levels, how much human activity was going on. ...

New cell type identified in cancer development

...ell types. Among them is a small subset of rather primitive cells that, like other stem cells in the body, are self-sustaining, self-renewing and multipotent, or capable of creating other types of cells and tissues. These cells are different from normal stem cells, however, in that injecting even as few as 10...

Paleontologists discover new mammal from Mesozoic Era

...rm, in contrast to its relatively shorter and very primitive limb and foot structures. The new mammal also has lumbar ribs, a rare feature among modern mammals. "The discoveries of exquisitely preserved Mesozoic mammals from China have built the evidence such that biologists and paleontologists are able to ...

Primitive yeast yields secrets of human cholesterol and drug metabolism

By first probing the way primitive yeast make cholesterol, a team of scientists has discovered a long-sought protein whose human counterpart controls cholesterol production and potentially drug metabolism. The collaborative study by investigators at Johns Hopkins University School of...

Stanford scientists make major breakthrough in regenerative medicine

... to any of these organisms. Sea squirt larvae have primitive spinal cords, distinguishing them in the greater chain of life and on the evolutionary ladder. Specifically, sea squirts, like humans, belong to a group of animals called chordates (organisms with some level of spinal cord development), and many scie...

Deep in the ocean, a clam that acts like a plant

...een plants is done by chloroplasts, descended from primitive single-celled organisms that were incorporated into other cells billions of years ago. "The energy from hydrogen sulfide is used to drive carbon fixation in much the same way that chloroplasts carry out carbon fixation," Eisen said. The symbiotic ...

Anti-fungal drug stops blood vessel growth

...nzyme for making fungal cholesterol, causing these primitive life forms to become fragile and break apart. It turns out that itraconazole can block the same enzyme in blood vessels, but the researchers aren’t positive if that’s the reason blood vessels stop growing, because related antifungal drugs had much lo...

Biologists call for better choice of model organisms in 'evo-devo'

...tic tree, or as a pointer to species with presumed primitive (ancestral) characteristics. Drs Ronald Jenner ...ase of the evolutionary tree does not make it more primitive and representative. "Equally, those that became separate species further down the evolutionary l...

'Killer' B cells provide new link in the evolution of immunity

...overed a unique evolutionary link between the most primitive innate form of immune defense, which has survived in fish, to the more advanced, adaptive immune response present in humans and other mammals. The finding, which appears in the online version of the October issue of Nature Immunology, represents an...

Tiny Tampa Bay fish key to evolution of immune system

... a screen and a bucket, scientists studying a tiny primitive fish that makes up 70 percent of the biomass in Ta...he immune response; specifically, it tells us that primitive organisms have more sophisticated immune systems than we previously thought," said X-ray crystallogr...

Selecting life: Scientists find new way to search for origin of life

... were they sufficiently concentrated to initiate a primitive version of metabolism? We now know that minerals select specific organic compounds out of solution, and can even distinguish between subtle properties such as chirality, binding a left-handed amino acid in preference to one that is right handed. Thes...

Two studies on bee evolution reveal surprises

.... Until now, many researchers believed the most primitive bees stemmed from the family Colletidae, which implies that bees originated in the Southern Hemisphere (either South America or Australia). However, the work of Danforth and his group suggests that the earliest branches of the bee's evolutionary tr...

Researchers give name to ancient mystery creature

...eeth, which resemble in superficial ways, those of primitive relatives of ungulates, the group of mammals which includes horses and cows. But despite that link to ungulates, which are traditionally herbivores, Horolodectes was thought to have dined on small insects and grubs. "It had sharp crests on the teeth ...

PNAS study reveals why organs fail following massive trauma

...rtooth tiger attack, meant immediate death for the primitive human. Modern man is more likely to survive sever...in human evolution. White blood cells of the more primitive innate system, like neutrophils and macrophages, form the first line of defense against disease. The...

A new male-specific gene in algae unveils an origin of male and female

...ings, which indicate that a gene underlying a more primitive system of reproduction was likely co-opted during evolution to participate in sex-specific sperm development, are reported by Hisayoshi Nozaki and colleagues at the University of Tokyo, Rikkyo (St. Paul’s) University, and Osaka University. The paper ...

Getting to the heart of the heart

...rstand the process of how things develop from very primitive embryonic stem cells to fully differentiated tissue, you have the potential to duplicate that process in the lab and make a tissue that a patient might need," says John Mayer, MD, a cardiovascular surgeon at Children's who is developing tissue-engine...

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