Pls could someone help thank you!! 3) Complete the sentences below about breathing: (6)
During inhalation the chest cavity changes shape and size. The contract which causes the rib cage to expand and pushes out the sternum (chest/breastbone). The will contract and will change shape from a concave or dome shape to a flattened shape. The pressure inside the chest cavity will be and therefore allows air to be sucked into the lungs. The air we breathe in is high in and but low in .

Ariver has different populations of lampreys and paddlefish. the paddlefish feed on zooplankton, while the lampreys feed on the paddlefish. humans living around the river hunt the paddlefish. what will happen to the ecosystem if the paddlefish are hunted in excess? a. the population of lamprey will decrease, while the population of paddlefish will increase. b. the population of paddlefish will decrease, while the population of zooplankton will increase. c. the population of paddlefish will increase, while the population of zooplankton will decrease. d. the population of lamprey will increase, while the population of zooplankton will decrease.