For lunch, Jane Doe consumed the following: a turkey sandwich on whole wheat bread with mayonnaise, lettuce, and tomato; potato chips; and apple juice.
(1) Trace the path of digestion through Jane from beginning to end.
Cheater.
The path of digestion through Jane Doe can be traced as follows:
1. Mouth: Jane begins the process of digestion by chewing her food. In her case, she starts with a turkey sandwich on whole wheat bread with mayonnaise, lettuce, and tomato, as well as potato chips. The chewing action breaks down the food into smaller pieces and mixes it with saliva.
2. Esophagus: Once Jane swallows, the food travels down her esophagus, a muscular tube that connects the mouth to the stomach. The food is moved down the esophagus through a process called peristalsis, which involves rhythmic contractions of the muscles in the esophagus walls.
3. Stomach: The food, now in the form of a food bolus, enters the stomach. The stomach secretes gastric juices, including hydrochloric acid and enzymes, to break down proteins and kill any harmful bacteria that may be present in the food. The contents of the stomach mix and churn with the help of muscular contractions, turning the food into a semi-liquid substance called chyme.
4. Small Intestine: The chyme is released from the stomach into the small intestine. The small intestine is where most of the chemical digestion and nutrient absorption takes place. Enzymes from the pancreas and bile from the liver and gallbladder are secreted into the small intestine to further break down complex carbohydrates, proteins, and fats into simpler molecules that can be absorbed by the body.
5. Absorption: The digested nutrients, such as sugars, amino acids, and fatty acids, are absorbed through the walls of the small intestine into the bloodstream. From there, they are transported to various cells and organs in the body, providing energy and building blocks for growth and repair.
6. Large Intestine: Anything that is not absorbed in the small intestine, such as fiber and undigested waste, moves into the large intestine. The large intestine's main function is to absorb water and electrolytes from the remaining material, forming solid waste or feces.
7. Rectum and Anus: The feces are stored in the rectum until it is eliminated through the anus during a bowel movement.
So, in summary, the path of digestion for Jane Doe's lunch starts from the mouth, moves through the esophagus and stomach for initial breakdown and digestion, continues through the small intestine for further digestion and nutrient absorption, then passes through the large intestine for water absorption, and finally exits the body through the rectum and anus.