Scientists have identified a previously undiscovered organelle inside microorganisms that live in the guts of ruminant animals. In a paper published in Science on 30 April 1, researchers describe an ...

Anatomy is the field of biology that studies the structure of living things. Anatomy focuses on the composition, structure and location of the parts of organisms tissues, organs and systems as well as ...

The penis is a male sexual organ. The shaft is the longest part of it. The head or glans is at the end of the shaft. The opening at the tip of the head, where urine and semen come out, is called the ...

The heart has four chambers that contract and relax in a specific rhythm to oxygenate blood and pump it throughout the body. The heart’s electrical system coordinates muscle contractions to maintain a ...

The kidneys help remove waste products from the body, maintain electrolyte balance, and regulate blood pressure. The kidneys are a pair of bean-shaped organs located below the rib cage, one on each ...

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