Afood web is shown above. what would most likely happen in this ecosystem if the shark population significantly increased?

Most probably the shark´s favorite food down the chain will be diminished, creating an imbalance in the ecosystem which in terms will affect all the other species living in that ecosystem.  

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.