Medical research

Micro-control of liver metabolism

Researchers at TIFR have discovered molecular anticipation of feeding in the liver that is essential to ensure that the body, after fasting, adapts to use incoming nutrients upon re-feeding. Their findings, published in the ...

Diseases, Conditions, Syndromes

High incidence of neonatal infections in Madagascar

Every year, 4 million children die before the age of one, mainly in resource-limited countries; one-third die from severe infections. The first month of life accounts for one third of deaths before the age of one. This situation ...

Immunology

T cells support long-lived antibody-producing cells

If you've ever wondered how a vaccine given decades ago can still protect against infection, you have your plasma cells to thank. Plasma cells are long-lived B cells that reside in the bone marrow and churn out antibodies ...

Other

Are promises made to living donors being upheld?

A new study finds some shortcomings by the transplant community in providing prompt access to transplantation for living kidney donors who later develop kidney disease and need a transplant. Donors are told that they will ...

Obstetrics & gynaecology

Optimal country-level C-section rate may be as high as 19 percent

The most commonly performed operation in the world is cesarean section, and rates of cesarean childbirth delivery vary widely from country to country, from as few as 2 percent to more than 50 percent of live births. The World ...

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Organism

In biology, an organism is any living system (such as animal, plant, fungus, or micro-organism). In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homeostasis as a stable whole. An organism may either be unicellular (single-celled) or be composed of, as in humans, many billions of cells grouped into specialized tissues and organs. The term multicellular (many-celled) describes any organism made up of more than one cell.

The terms "organism" (Greek ὀργανισμός - organismos, from Ancient Greek ὄργανον - organon "organ, instrument, tool") first appeared in the English language in 1701 and took on its current definition by 1834 (Oxford English Dictionary).

Scientific classification in biology considers organisms synonymous with life on Earth. Based on cell type, organisms may be divided into the prokaryotic and eukaryotic groups. The prokaryotes represent two separate domains, the Bacteria and Archaea. Eukaryotic organisms, with a membrane-bounded cell nucleus, also contain organelles, namely mitochondria and (in plants) plastids, generally considered to be derived from endosymbiotic bacteria. Fungi, animals and plants are examples of species that are eukaryotes.

More recently a clade, Neomura, has been proposed, which groups together the Archaea and Eukarya. Neomura is thought to have evolved from Bacteria, more specifically from Actinobacteria.

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