Phoebe confronts Ursula after breaking Joey's heart. She is Phoebe's "evil" identical twin.

Dr. Murphy tries to figure out why a pregnant lady's body is attacking her child.

Schmidt and Jenko fail to prove their synergy to the Yang twins. If anything, they show how different they are from each other through their word choice.

This clip illustrates how different breeds of dogs were made by artificial selection. Neil deGrasse Tyson also discusses evolution's role in this process.

Hank explains that heredity is the passing on of genetic traits from parents to offspring. He makes mention to Gregor Mendel, who found that inheritance follows particular patterns. Key Words: Classical Genetics, Chromosomes, Gene, Polygenetic Trait, Pleiotropic, Allele, Somatic, Diploid