Nutrition Chapter 3 -

Peristalsis

1. the involuntary constriction and relaxation of the muscles of the intestine or another canal, creating wave-like movements that push the contents of the canal forward.

How many hours go by before the body starts absorbing nutrients?

3-4 hours

Where does most absorbtion occur?

The small intestine

Organ/Gland: Salivary Gland

Target Organ: Mouth

Organ Secretion: Saliva

What is the action that occurs with these organs?

Fluids ease swallowing; salivary enzymes break down some carbohydrates.

Organ/Gland: Gastric Glands

Target Organ: Stomach

Organ Secretion: Gastric Juice

What is the action that occurs with these organs?

Fluid mixes w/bolus; hydrochloric acid uncoils (denatures) proteins, enzymes digest proteins, mucus protects stomach cells

Organ/Gland: Pancreas

Target Organ: Small Intestine

Organ Secretion: Pancreatic Juice

What is the action that occurs with these organs?

Bicarbonate neutralizes acidic gastric juices; pancreatic enzymes digest carbohydrates, fats, and proteins.

Organ/Gland: Liver

Target Organ: Gallbladder

Organ Secretion: Bile

What is the action that occurs with these organs?

Bile is stored until needed.

Organ/Gland: Intestinal (crypt) glands

Target Organ: Small Intestine

Organ Secretion: Intestinal Juice

What is the action that occurs with these organs?

Intestinal enzymes digest carbohydrates, fat, and protein fragments; mucus protects the intestinal wall.

Organ/Gland: Gallbladder

Target Organ: Small Intestine

Organ Secretion: Bile

What is the action that occurs with these organs?

Bile break down fat so that enzymes can access it and digest it.

Vascular System

The exchange of oxygen and nutrients with carbon dioxide and waste.

The Liver

Defends the body by detoxifying substances that could possibly cause harm and prepare wastes for excretion

The Lymphatic System

Provides one-way route for fluid from tissue spaces to enter blood

What does the mouth do in the digestive tract?

Chews food and mixes it with saliva to begin digestion.

What does the pharynx do?

Directs food from the mouth to the esophagus.

What does the epiglottis do?

The epiglottis protects the airway when swallowing.

What does the trachea do?

It allows air to pass to and from the lungs

What does the Esophagus do?

It passes food from the mouth to stomach.

Esophageal Sphincter is the passage that passes food from the mouth to the esophagus, then to the stomach. What does it prevent?

It prevents backflow from the stomach (one-way system) to the esophagus and from esophagus to mouth.

What does the stomach add to the food to digest it? What actions does it do with the substance(s) added?

Acid, enzymes, and fluid are added to the food to digest it. The stomach then mixes, churns, and grinds food to a liquid mass.

What do sphincters do to the digestive tract?

Sphincters keep the digestive tract a one-way path. This way the food cannot be moved back the way it came.

What does the liver help digest?

The Liver manufactures bile salts, detergent-like substances, to help with digesting fats.

The gallbladder store bile until ?

Bile is stored until dietary fat is present in the duodenum.

The bile duct conducts bile from the ______ to the ______.

Conducts bile from the gallbladder to the small intestine

Duodenum

Continues digesting food after it leaves the stomach.

What does the small intestine use to digest the energy and nutrients?

Secretes enzymes that digest all energy yielding nutrients to their basic building blocks; Cells that absorb nutrients into the bloodstream.

What does the pancreas build?

It manufactures enzymes that are delivered to the lumen of the small intestine to digest all energy yielding nutrients and release bicarbonate to neutralize acid chyme that enters the small intestine.

What are the two things the large intestine does"?

1. Reabsorbs water and minerals.

2. Passes waste, (fiber, bacteria, and unabsorbed nutrients) along with water to the rectum.

Rectum

Stores waste prior to elimination.

Anus

Holds rectum closed, opens to allow elimination of waste.

What do undigested residues (fibers) do?

1. Continue through GI tract

2. Exercise the GI muscles

3. Retain water

GI Tract

Gastrointestinal tract - the path the body has to gain nutrients from the food taken in and the release of waste.

What are the four things gastrointestinal bacteria (flora), depend on?

1. pH

2. Diet

3. Peristalsis

4. Other microorganisms

What is the response to the hormone?

Hormone: Gastrin

Responds to: Food in the stomach

Secreted By: Stomach Wall

Stimulates: Stomach Glands

Hydrochloric acid is secreted into the stomach.

What is the response to the hormone?

Hormone: Secretin

Responds to: Acidic chyme in the SI

Secreted By: Duodenal Wall

Stimulates: Pancreas

Bicarbonate-rich juices secreted into the SI.

What is the response to the hormone?

Hormone: Cholecystokinin

Responds to: Fat or protein in the SI

Secreted By: Intestinal Wall

Stimulates: Gallbladder and Pancreas

Bile secreted into the duodenum. Bicarbonate and enzyme-rich juices secreted into the SI

The system is sensitive and responsive to environmental conditions which provides immunity. This depends on what three things?

1. Healthy Blood Supply

2. Lifestyle Factors

3. Diet

What are five Common Gastrointestinal Conditions?

Diarrhea, Vomiting, Belching, Ulcers, Heart Burn

What is Celiac Disease?

Celiac disease is an autoimmune disease that makes the stomach unable to digest the gluten enzyme very well. It needs a full gluten free diet.

What influences constipation and what can be used to prevent it?

Influenced by: Health, diet, fluid intake (water), and physical activity.

Things that help prevent it: Diet and fiber intake (25-38 grams/day), staying physically active, and staying well hydrated.

What is Inflammatory Bowel Disease?

A disorder that has a constant, long standing inflammation in the digestive tract.