How does the food change in consistency and form?
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As food moves through the entirety of the digestive system, its consistency and form changes constantly. As it enters the mouth, it is broken down into smaller pieces. Salivary enzymes then turn broken down pieces into a bolus of food. It then passes through the esophagus and the pharynx then into the stomach. The muscles of the stomach wall compresses the food and mixes it with gastric juices, forming a fluid chyme. Finally, food is sent to the small and large intestines to fully digest it and form feces for excretion.
How could the body absorb the nutrients from the foods we eat?
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The small intestines serve as the major site of absorption of food and nutrients as it absorbs 90% of all nutrients and water. It contains structures such as villi and microvilli which help absorb nutrients. The large intestine absorbs remaining nutrients.