Marc learns about the growth of corn and pigs at the Bakers Akers farm. Trini sits in on an expectant mother's ultrasound. At the Bronx Zoo, Lisa goes on the rounds with a young veterinarian feeding baby animals.Film inserts: Time-lapse growth of peanut plant and pea plant; kids explain the birth of tadpoles and their growth into frogs; the human embryo develops into a baby; human birth.ANIMATION: Human from conception to birth. (Concludes in next episode.)THE BLOODHOUND GANG: ""The Case of the Secret Message, Part One."" Vikki recovers a lady's purse, which contains only a message written in salt-water solution. (Concludes in next episode.)