(materials). A solvent in whose molecules there is either a permanent separation of positive and negative charges, or the centers of positive and negative charges do not coincide; these solvents have high dielectric constants, are chemically active, and form coordinate covalent bonds; examples are alcohols and ketones.1  Facebook.materials). A solvent in whose molecules there is either a permanent separation of positive and negative charges, or the centers of positive and negative charges do not coincide; these solvents have high dielectric constants, are chemically active, and form coordinate covalent bonds; examples are alcohols and ketones.
The bottleneck effect. The bottleneck effect is an extreme example of genetic drift that happens when the size of a population is severely reduced. Events like natural disasters (earthquakes, floods, fires) can decimate a population, killing most indviduals and leaving behind a small, random assortment of survivors.
(In biology) The bottleneck effect happens when the size of a population or even an entire species is suddenly reduced, with lasting effects on at least one generation.A popu â¦ lation bottleneck may occur after an epidemic, drought, fire, hunting, or other destructive events.ottleneck effect is an evolutionary event in which population size is radically reduced because of catastrophic events. founder effect occur when few individuals migrate fr â¦ om main population and establishes a separate population in new geographical location. both of these are special cases of genetic drift.