The ECM commands the EVAP Purge Solenoid OFF once the system has reached a predetermined level of vacuum. This test verifies if a vacuum can be achieved in the EVAP system. Failure to develop a vacuum may be caused by a large leak or a restriction.
Our subspecies has evolved since 500 years ago. As one example, take the changed prevalence of genetic diseases. As these are caused by alleles (and therefore the frequency of the relevant alleles has changed), and evolution is the change in allele frequencies in gene pools over generations, this is biological evolution. Humans are apes.
A: The phrase multiple alleles in biology refers to a series with at least three allelic or alternative forms of a particular gene, with only two that are able to exist in a diploid individual. There are two alleles present in an individual: a paternal and a maternal allele.