Encyclopedia of Biology

(704 million years); uranium 238–lead 206 (4.47 bil- lion years); carbon 14-nitrogen 14 (5,730 years). See alsoELEMENT. radiocar ...

technique. Good for dates between 10,000 and 230,000 years. radionuclide A radioactive nuclide. The term nuclideimplies an atom ...

which diminish the immune attack and the resulting inflammation. Toxicodendron Dermatitis When people get urushiol—the oil prese ...

have the ability to regenerate lost limbs and demon- strated that corals were animals, not plants. In 1735 he introduced the con ...

individual will be inclined to perform the same act back or to another individual. The individual giving does not necessarily ex ...

reduction The part of a redox reaction where the reactant has a net gain of electrons and in which a dif- ferent reactant must o ...

increasing nor decreasing, then the genotype with a rel- ative fitness of more than one will increase in frequen- cy, whereas if ...

G G G G G G G T T T T T T T T T T T T T T A A A A A A A A A A A A A A A C C C C C C C C C C C C G G G T T T A A A C C C G G T A ...

resonance Raman spectroscopy A spectroscopic technique increasingly used in bioinorganic chemistry for characterization and assi ...

them to the optic nerve by using a set of nerve cells— horizontal, bipolar, amacine, and retinal ganglion cells—finally leading ...

controlled by two closely linked genes on chromosome Can lead to serious medical complications between a mother and her develop ...

AUTOTROPHICbacteria. It catalyzes the synthesis of 3- phospho-D-glycerate from ribulose bisphosphate and also the oxidation of r ...

In 1945 Richards was appointed professor of medicine at Columbia University and visiting physician and director of the First (Co ...

RNA polymerase The enzyme that directs the link- ing of ribonucleotides during transcription. RNA See RIBONUCLEIC ACID. RNA proc ...

Robbins, a plant physiologist who became director of the New York Botanical Gardens, and Christine (née Chapman). He received a ...

Service in 1881. Ross married Rosa Bessie Bloxam in 1889 and they had two sons and two daughters. He began the study of malaria ...

roundworm SeeNEMATODE. royal jelly A milky white creamy material, thick and nutritious, secreted by the hypopharyngeal glands of ...

saltatory conduction The quick transmission of a nerve impulse along an axon by “jumping” from one node of Ranvier to another. s ...

grassland dominates. A midlatitude variant, the park- land, is located in the drier portions of the humid con- tinental climate, ...

opment in a plant but are parts of the normal part of a plant’s metabolism. They often serve to discourage being eaten by making ...