Chapter 1: An Overview of the Process of Digestion Flashcards
What is the process of breaking down food into nutrients that cells can use?
The process includes several steps: ingestion (putting food into the mouth), mastication (chewing), and deglutition (swallowing).
What is mastication?
Mastication is the process of physically breaking down food by the actions of the teeth, tongue, lips, and facial muscles during chewing.
What is deglutition?
Deglutition, or swallowing, is the process of moving chewed food from the mouth through the pharynx and into the esophagus.
What happens to the food after it is swallowed?
After swallowing, the food travels down the esophagus into the stomach, where it is stored and further broken down.
What is the role of the epiglottis during swallowing?
The epiglottis closes over the top of the trachea during swallowing to prevent food from entering the lungs.
What is the role of the stomach in digestion?
The stomach is mostly concerned with physically changing food through mechanical digestion by continuing to break it apart.
What is chemical digestion?
Chemical digestion involves breaking down food molecules into their individual components, such as amino acids from proteins, fatty acids from fats, and glucose from carbohydrates.
Where does chemical digestion primarily occur?
Chemical digestion primarily occurs in the small intestine.
What are the enzymes involved in chemical digestion?
Enzymes ending with “-ase” are used in the process of chemical digestion. For example, amylase breaks down carbohydrates, protease breaks down proteins, and lipase breaks down fats.
Where does chemical digestion of carbohydrates and proteins begin?
Chemical digestion of carbohydrates begins in the mouth with the action of salivary amylase, while chemical digestion of proteins begins in the stomach with the action of pepsin.
What is absorption in the context of digestion?
Absorption is the process of small molecules, broken down from food, entering the bloodstream to be delivered to cells.
Where does absorption primarily occur?
Absorption primarily occurs in the small intestine, where most of the nutrients are absorbed into the bloodstream.
What happens to nutrients after absorption in the small intestine?
After absorption, nutrients are transported to the liver through the bloodstream, while what can’t be used is left behind to become feces in the large intestine.
What is the role of the large intestine in digestion?
The large intestine primarily removes water from the chyme (partially digested food) that enters it, forming feces, which are then eliminated from the body through defecation.
Describe the process of defecation.
Defecation is the process of feces leaving the body. It occurs through the rectum (the last part of the large intestine) and out of the anus.
