Besides cardiac muscle, what other tissue type possesses pacemaker cells?

Smooth muscle is another type of tissue that possesses pacemaker cells beside the cardiac mucle. It has a pacemaker activity that can remove the vibration of waves without the present of some external stimuli. In addition, smooth muscle can also start a spontaneous contraction. 

not the best question format lol but what i think might as scale color is controlled by a single gene with two alleles, the green allele and the yellow allele. when moths that are homozygous for green scales are mated with moths that are homozygous for yellow scales, 100% of the offspring have green scales.

when a reversible reaction is occurring in both directions at the same rate; the products and reactants do not change in concentration. a chemical reaction where the compound is broken into its constituent parts.