1. true or false: Biomagnification results in higher amounts of toxic substances for organisms higher on the food chain. 2. true or false: An overgrowth of microbes can decrease dissolved oxygen levels to the point where organisms cannot survive.

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.

answer; aerobic conditions; citric acid cycle (krebs cycle) electron transport chain;         anaerobic conditions; fermentation; both glycolysis;