What physiological process does the bolus undergo after being swallowed?

After being swallowed, the bolus undergoes the physiological process of digestion. Digestion begins in the mouth as salivary enzymes start breaking down carbohydrates, but it continues in the stomach and small intestine, where the bolus is further mixed with digestive juices. These juices, containing acids and enzymes, help to break down food into its nutrient components, allowing the body to absorb essential vitamins, minerals, and macronutrients.

This process is crucial for the body's ability to utilize food for energy, growth, and repair. Once the bolus has been digested into a semi-liquid form called chyme, it can then move into the small intestine, where further digestion and absorption occur.

The other processes listed, such as absorption, dissolution, and elimination, are subsequent steps or different aspects of the digestive process. Absorption specifically refers to the uptake of nutrients from the digested food into the bloodstream, while elimination is the final step in the digestive process, involving the removal of waste products from the body. Dissolution is more about the process of solubilizing substances, which does not accurately describe what happens to the bolus immediately after swallowing. Therefore, digestion is the most fitting answer to describe the physiological changes that occur after swallowing the bolus.