1. How does the food change in consistency and form?
- During the digestion process, food undergoes changes in form and consistency. Chewing breaks it down in the mouth, where it combines with saliva to form a mushy mass called a bolus. Through gastric acids and churning, it becomes chyme, a semi-liquid material, in the stomach. Bile and enzymes further break it down in the small intestine so that nutrients may be absorbed. In the large intestine, the leftover undigested material forms into feces for excretion.
2. How could the body absorb the nutrients from the foods we eat?
- The small intestine is where the body absorbs nutrients the most. Food that has been digested separates into components, such as fatty acids, glucose, and amino acids. These chemicals enter the bloodstream or lymphatic system through specialized cells that traverse the gut walls. The small intestine's villi and microvilli, which resemble tiny fingers, enhance surface area and improve absorption efficiency. After that, nutrients are delivered to cells for growth, repair, and energy.