Seafood is a staple in nearly every Chilean's diet. Shellfish such as loco (abalone), erizo (sea urchin) and piure (an unusual red invertebrate) join more widely known fish, including sardines, salmon, congrio (conger eel) and atÃºn (yellowfin tuna).
To work efficiently, pipes need a way of regulating how much fluid can pass through them; they also need a way of switching the flow off completely. That's the job that valves do: valves are like mechanical switches that can turn pipes on and off or raise or lower the amount of fluid flowing through them.
Heart valves function to ensure a one-way flow of blood through the heart. The valves are not made of muscle, but rather are composed of sheets of tough connective tissue (leaflets) that act like flaps. The heart valves open and close passively because of pressure differences on either side of the valve.