Digestive system Flashcards
What are the major stages of digestion?
Ingestion, mechanical and chemical digestion, absorption, and elimination.
What is the difference between mechanical digestion and chemical digestion?
Mechanical digestion involves physically breaking down food (e.g., chewing, stomach churning), while chemical digestion involves breaking down food with enzymes and acids.
What is peristalsis?
Peristalsis is the series of wave-like muscle contractions that moves food through the digestive tract.
Describe the overall pathway food takes through the digestive system.
Food enters the mouth, travels down the esophagus, enters the stomach, moves into the small intestine for further digestion and absorption, then into the large intestine for water absorption and feces formation, and finally is expelled through the rectum and anus.
What is the primary function of the mouth in digestion?
The mouth initiates digestion by mechanically breaking down food through chewing and chemically beginning carbohydrate digestion with salivary amylase. It also aids in taste.
How does food move from the mouth to the stomach?
Food is swallowed and moved along the esophagus by peristalsis.
What is the function of the esophagus?
The esophagus is a muscular tube that transports food from the pharynx to the stomach using peristaltic movements.
What are the main functions of the stomach?
The stomach stores food, mechanically churns it, and chemically digests proteins using acids and enzymes, turning the food into a semi-liquid mixture called chyme.
Name one key structure in the stomach involved in digestion and its function.
Gastric pits secrete acid and enzymes to help break down food.
What is the primary role of the small intestine?
The small intestine is responsible for the majority of chemical digestion and absorption of nutrients.
What are the three parts of the small intestine?
The duodenum, jejunum, and ileum.
How do enzymes contribute to digestion in the small intestine?
Enzymes from the pancreas and bile from the liver (stored in the gallbladder) help break down fats, carbohydrates, and proteins, facilitating nutrient absorption.
What is the function of the large intestine?
The large intestine absorbs water and electrolytes from indigestible food matter and compacts the remaining material into feces.
What role does the rectum play in digestion?
The rectum stores fecal matter until it is ready to be expelled from the body.
What are the digestive functions of the liver?
The liver produces bile to emulsify fats, processes nutrients absorbed from the small intestine, and detoxifies various metabolites and chemicals.
What is the function of the gallbladder in digestion?
The gallbladder stores and concentrates bile produced by the liver and releases it into the duodenum when needed.
How does the pancreas aid in digestion?
The pancreas produces digestive enzymes (like lipase, amylase, and proteases) that break down fats, carbohydrates, and proteins, and it secretes bicarbonate to neutralize stomach acid in the duodenum.
