One of the most remarkable examples of cell communication is the fight or flight response. body handle extraordinary situations. responses involved in the fight or flight response. place in the movie. 0:16 An environmental signal travels into the brain. a nerve impulse to the hypothalamus (not shown).
Umbilical cord. In placental mammals, the umbilical cord (also called the navel string, birth cord or funiculus umbilicalis) is a conduit between the developing embryo or fetus and the placenta.
During most of the pregnancy, the expectant mother nourishes her embryo/fetus through the placenta, the organ of pregnancy that connects the uterus to the embryo/fetus via the umbilical cord. The role of the placenta is to transfer nutrients and oxygen from the mother's bloodstream to the embryo/fetus.