Question

explore it! place your hand over your chest and sit still while you count to 30. 3. what did your chest do as you rested? was this movement voluntary or involuntary? place your hand on your chest once again. take deep, controlled breaths while you count to 30 counting each breath. think about how this breathing is different than the first breathing exercise. 4. is this breathing voluntary or involuntary, and why?

Explanation:

When resting, the chest rises and falls due to involuntary breathing controlled by the respiratory center in the brainstem to maintain gas - exchange. In the second exercise, taking deep, controlled breaths is voluntary as it is consciously initiated and regulated by the cerebral cortex.

Answer:

1. The chest rose and fell. It was involuntary because it is a normal, automatic process controlled by the body's respiratory center to maintain gas - exchange without conscious effort.
2. This breathing is voluntary because it is consciously initiated and controlled by the person, using the cerebral cortex to regulate the rate and depth of breaths.