Unlike natural selection, genetic drift does not depend on an allele's beneficial or harmful effects. Instead, drift changes allele frequencies purely by chance, as random subsets of individuals (and the gametes of those individuals) are sampled to produce the next generation.
PH meter, which is a device used to measure hydrogen-ion activity in the solution. A PH meter is a voltmeter stuck to a pH electrode and a reference electrode. -maclittleseed
A trait is the organism's feature. So, a trait would be eye color. A phenotype would be hazel. An allele is a gene. It can be recessive or dominant.
