Final answer:
The term 'Bolus' in nutritional physiology refers to the chewed and saliva-mixed food that is ready to be swallowed, representing food in the stage post-mastication and pre-swallowing.
Step-by-step explanation:
The nutritional physiology term Bolus refers to the soft mass of chewed food that has been mixed with saliva in the mouth and is ready to be swallowed. Ingestion is the first step in the process of obtaining nutrition and energy from food, where food is taken in through the mouth, and through mastication or chewing, it is prepared into a bolus. This process involves both mechanical breakdown by the teeth and chemical breakdown with the enzymes present in saliva, ultimately creating a bolus suitable for swallowing and passage through the esophagus.