| zwitter hypothesis | That an amphoteric molecule (e.g., an amino acid) has, at its isoelectric point, equal numbers of positive and negative charges, thus becoming a zwitterion. (05 Mar 2000) |
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| frustration-aggression hypothesis | The theory that frustration may lead to aggression, but that aggression is always the result of some form of frustration. (05 Mar 2000) |
| Lyon hypothesis | <genetics> Hypothesis, first advanced by Lyon, concerning the random inactivation of one of the two X chromosomes of the cells of female mammals. In consequence females are chimaeric for the products of the X chromosomes, a situation that has been exploited in female Negroes (who are heterotypic for isozymes of glucose 6 phosphate dehydrogenase) as a means to confirm the monoclonal origin of papillomas and of atherosclerotic plaques. (20 Mar 1998) |