Dictionary

rebound The reversal of response upon withdrawal of a stimulus.

rebound effect The production of increased negative symptoms when the effect of a drug has passed or the patient no longer responds to the drug. If a drug produces a rebound effect, the condition it was used to treat may come back even stronger when the drug is discontinued or loses effectiveness.

recalcitrant Stubborn. For example, a recalcitrant case of pneumonia stubbornly resists treatment.

recent memory See memory, short-term.

receptor 1 In cell biology, a structure on the surface of a cell or inside a cell that selectively receives and binds a specific substance. For example, there are insulin receptors and low-density lipoprotein (LDL) receptors. 2 In neurology, the terminal of a sensory nerve that receives and responds to stimuli.

receptor, visual The layer of rods and cones, the visual cells, of the retina.

recessive A genetic trait that appears only in individuals who have received two copies of a mutant gene, one copy from each parent. The individuals with a double dose of the mutated gene are called homozygotes. Their parents, each with a single dose of the mutated gene, appear normal and are called heterozygotes, or gene…

recessive, autosomal See autosomal recessive trait.

recipient In medicine, someone who is given something, such as a blood transfusion or an organ transplant, that is derived from another person (the donor).

recombinant A person with a new combination of genes, a combination not present in either parent, due to parental recombination of those genes.

recombinant clone A clone that contains recombinant DNA.

recombinant DNA molecules A combination of DNA molecules of different origin that are joined using recombinant DNA technology.