_________ occurs when the external intercostal muscles contract, pulling the ribs up and expanding laterally.

A. Mastication: Mastication is the mechanical chewing of food that occurs in the mouth to break food into smaller pieces -not related to bile emulsifying fats.
B. Peristalsis: Peristalsis are wave-like smooth muscle contractions that propel contents through the GI tract -helps move chyme but does not chemically/physically disperse fat droplets like bile does.
C. Emulsification: Emulsification is the process by which bile salts surround and break large fat globules into many small droplets, increasing surface area for lipase action.
D. Deglutition: Deglutition is the act of swallowing, moving a bolus from the mouth into the pharynx and esophagus -not the process of bile acting on lipids.

A. Converted to carbon monoxide: CO (carbon monoxide) is a different gas and is not a product or transport form of CO₂.
B. Bind to myoglobin: Myoglobin primarily binds O₂ within muscle cells; CO₂ transport by myoglobin is not a main mechanism.
C. Binds to hemoglobin: CO₂ can bind to hemoglobin (forming carbaminohemoglobin) as one transport form.
D. Converted to bicarbonate ions: Most CO₂ is converted to bicarbonate (HCO₃⁻) in red blood cells and transported in plasma.
E. Dissolved in plasma: A small proportion of CO₂ is carried dissolved directly in plasma.