The instantaneous and automatic fear response we experience when unexpectedly stumbling upon a snake illustrates the importance of the a. hippocampus. b. pituitary gland. c. hypothalamus. d. amygdala.

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.