Describe Why natural selection against an unforgivable recessive allele is a slow process

A recessive allele only shows up in the phenotype (is only manifested physically) if there is no paired dominant allele to cover it up. Natural selection against a recessive allele can only act when the recessive allele shows up in the phenotype. This means that there are a lot of organisms carrying an invisible recessive allele around. As long as the recessive is invisible (paired with a dominant allele) natural selection can't find it and can't do its job.

Neurotransmitters are messengers responsible for communication between neurons. they are released from synaptic vesicles and are received by receptors.  the communication is referred to as neurotransmission. the following statement is true about neurotransmitters: a. they're stored in synaptic vesicles in the axon.