A leavening agent is an organism or substance that when added to a dough[?] of flour and water causes it to "rise" by evolving carbon dioxide or other gasses that become trapped as bubbles[?] within the dough.
... (25-38 mm) long and opens in the vulva between the clitoris and the vaginal opening.
In the human male, the urethra is about 8 inches (200 mm) long and opens at the end ...