- expression
- 1. Squeezing out; expelling by pressure. 2. Mobility of the features giving a particular emotional significance to the face. SYN: facies (3) [TA]. 3. Any act by an individual. 4. Something that manifests something else. 5. The act of allowing information to become manifest. 6. A mathematical function consisting of a combination of constants, variables, other functions, and mathematical operations.- differential gene e. gene e. that responds to signals or triggers; a means of gene regulation; E.G., effects of certain hormones on protein biosynthesis.- gene e. 1. the detectable effect of a gene. 2. appearance of an inherited trait; for many genetic ( e.g., recessiveness, hypostasis, parastasis) and environmental (the absence of pertinent challenges) reasons, a gene may not be expressed at all. In those circumstances, it will have no impact on Darwinian evolution.- integrated rate e. an equation of a chemical or enzyme-catalyzed reaction for the entire progress curve.- e. library a collection of plasmid or phage containing a representative sample of cDNA or genomic fragments that are constructed in such a way that they will be transcribed and translated by the host organism (usually bacteria).
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ex·pres·sion ik-'spresh-ən n1 a) something that manifests, represents, reflects, embodies, or symbolizes something else <the first clinical \expression of a disease>b ) (1) the detectable effect of a gene <gene \expression can be controlled by regulatory proteins that bind to specific sites on DNA (Mark Ptashne)> (2) EXPRESSIVITY2) facial aspect or vocal intonation as indicative of feeling3) an act or product of pressing out* * *
ex·pres·sion (ek-spreshґən) [L. expressio] 1. the aspect or appearance of the face as determined by the physical or emotional state. 2. the act of squeezing or evacuating by pressure. 3. gene e.
Medical dictionary. 2011.