Digestive System Flashcards
Alimentary canal/digestive tube consists of:
Mouth Pharynx Esophagus Stomach Small intestine Large intestine Rectum Anus
Accessory organs of digestion include:
Liver
Pancreas
Gallbladder
How is food ingested?
- Food is broken down by the teeth and tongue in mastication (chewing)
- Amylase in saliva helps to digest carbs
- Pharynx force a bolus into esophagus and food is swallowed
- Gastric glands secrete hydrochloric acid that breaks down food
- Stomach muscle churns and mixes food bolus, turning it into chyme
Function of saliva:
Lubricates and dilutes chewed food
4 main layers of the digestive track from innermost to outermost:
Mucous
Submucous
Muscular
Serous
Amylase:
Enzyme in saliva that starts the digestion of complex carbohydrates
Chyme:
Mass of food that gets turned into a soupy substance
Role of small intestine in digestion:
- Digestion and absorption of food
- Food is acted on by enzymes from the small intestine, pancreas, and bile from the liver
How does the pancreas contribute to digestion?
Contributes water to dilute chyme and bicarbonate ions to neutralize the acid from the stomach
Small intestine consists of:
Duodenum, jejunum, and ileum
Where are nutrients absorbed?
Where do all nutrients then go?
Walls of small intestine
Enter hepatic portal vein to be routed to the liver for decontamination
Villi:
Small fingerlike projections that increase surface area of the intestinal wall
Role of large intestine in digestion:
Reabsorbs water and stores and eliminates undigested food. Intestinal bacterial flora is found here.
Large intestine is arranged into 5 portions:
Ascending colon Transverse colon Descending colon Sigmoid colon Rectum
Bile is secreted into which organ?
Small intestine
