Digestion, Absorption, and Transport

Flashcards about Digestion, Absorption, and Transport

What is digestion?

The breakdown of food into nutrients.

What is the order in which food passes through the digestive system?

Mouth, Esophagus, Stomach, Small intestine, Large intestine, Rectum, Anus

What is the lumen of the intestine?

The inner space of the intestines.

What is a bolus?

The mass of swallowed food.

What is Chyme?

The semiliquid mass of partly digested food that passes from the stomach through the pyloric sphincter into the duodenum.

What are the five basic taste sensations?

Sweet, sour, bitter, salty, and umami (savory).

What two sphincter muscles control movement in the esophagus and stomach?

Upper esophageal sphincter and Lower esophageal sphincter

What fluids enter the small intestine via the common bile duct?

Fluids from the pancreas and gallbladder.

What valve allows passage from the small to the large intestine?

Ileocecal valve

What is segmentation?

Inner circular muscles contract in the small intestine to mix chyme with digestive juices.

What is peristalsis?

Outer longitudinal muscles push chyme forward in the small intestine.

What are the five organs that secrete digestive juices?

Salivary glands, stomach, pancreas, liver, and small intestine.

What are enzymes?

Protein catalyst facilitating chemical reactions.

What is Hydrolysis?

Breaks down substances by the addition of water.

What is the role of saliva?

Moistens food; initiates carbohydrate digestion; plays a protective role.

What does gastric juice do?

Acts primarily in protein digestion, made of water, enzymes and hydrochloric acid.

What does mucus do in the stomach?

Protects stomach wall cells from acid.

What does sodium bicarbonate do?

Neutralizes acidic chyme.

What is bile?

Produced by the liver, stored in the gallbladder, emulsifies fat.

What does fiber do in the Digestive System?

Exercise intestinal muscles.

What is the function of the Colon?

Absorbs water and recycles dissolved salts.

What is the primary function of the Small Intestine?

Majority of Nutrient Absorption

What are the absorption techniques in the small intestine?

Simple diffusion, facilitated diffusion, active transport.

What is the function of Villi?

Select and regulate nutrients absorbed.

What is the function of Microvilli?

Enzymes and “pumps”.

What is the function of Crypts?

Secretion of intestinal juices.

What is the function of Goblet cells?

Mucus secretion.

Where do water-soluble nutrients and small fat products transport?

Bloodstream to liver.

Where do large fat products and fat-soluble vitamins transport?

Lymphatic system to bloodstream

What is the function of the Bloodstream?

Delivers oxygen and nutrients, removes carbon dioxide and wastes.

What is the function of the Lymphatic System?

Collects fluids.

What do prebiotics do?

Encourage microbial growth.

What do probiotics do?

Live microbes.

What are the main GI hormones?

Gastrin, Secretin, Cholecystokinin (CCK)

What causes choking?

Food in the trachea.

What is diarrhea?

Frequent watery stools.

How can you prevent constipation?

High-fiber diet, plenty of fluids, regular exercise.

What causes intestinal gas?

Bacterial fermentation of fiber and starch in the large intestine.

What causes ulcers?

Bacterial infection.

How do you treat an Ulcer?

Take medicine as prescribed by your physician, avoid coffee and caffeine- and alcohol-containing beverages, avoid foods that aggravate your ulcer. Minimize aspirin, ibuprofen, and naproxen use. Refrain from smoking cigarettes.