figure 15.19 summary results from wt and mutant parabiotic mice. parabiotic mice in all pair-wise combinations of wt, ob, and db mice. parabiotic mice lived for several months under free-feeding conditions before the end of the experiment when investigators collected measurements. figure 15.19 shows the outcomes from experiments designed to explore the mammalian lipostat. which of the following statements are true? figure 15.19 summary results from wt and mutant parabiotic mice. parabiotic mice in all pair-wise combinations of wt, ob, and db mice. parabiotic mice lived for several months under free-feeding conditions before the end of the experiment when investigators collected measurements. the lipostat is regulated by blood cells as shown through parabiotic mice. db mice have a toxic compound in their blood, but they are resistant to the toxin. db and ob mice have different mutant alleles of the same gene. db mice lack a receptor whereas ob mice lack the ligand.