Discuss the process of digestion ?
Digestion breaks down food into its basic nutrients so that these nutrients can be absorbed and transported to the cells.
Once absorbed, these nutrients can be used to fuel our cells for growth, fight infection and provide energy to our muscles and our brain to perform daily activities.
What is the gastrointestinal tract?
A long hollow tube containing several layers that begins with the mouth and ends at the anus.
What are the three processes that the body can use to absorb nutrients from the GI tract into the blood or lymph system and eventually into the cells?
1. Passive Diffusion - substances move easily in and out of cells with out the use of energy.
2. Facilitated Diffusion - special protein carriers are needed to help substances cross into or out of the cell. No energy is required.
3. Active Transport - energy is needed to get the substance into or out of the cell.
What kind of stimuli initiatates the digestive system before any food even enters the mouth?
1. Cognition - thoughts about food can start the flow of saliva.
2. Sound - hearing a description of the meal.
3. Odor - the smell of food stimulates your hunger response and aids in the taste of food.
4. Appearance - seeing the food.
5. Taste - or mouth feel begins as the food enters your mouth.
What are the five flavors that can be tasted?
Sweet, sour, salty, bitter and umami (a meaty flavor)
What is the role of the salivary glands?
They secrete saliva into the mouth which contains mucus, enzymes and other substances.
Salivary amylase breaks down starch and lingual lipase begins to act on fats. During this process, mucus is being mixed with the food particles to lubricate, and make it easy to swallow a mouthful of food.
What is the esophageal sphincter?
This is a circular muscle that constricts (closes) once food moves through to the stomach to prevent backflow of stomach contents into the esophagus.
In the stomach the food particles are mixed with _____________
gastric juice and enzymes... The acid in the gastric juice prepares proteins for digestion and activates enzymes
Pepsin is an enzyme that breaks down proteins
Gastric lipase is an enzyme that begins fat digestion
What hormone controls the overall process of the release of acidsa and enzymes in the stomach?
Gastrin plays a major role in controlling the concentration of acid in the stomach
What is intrinsic factor?
a substance produced in the stomach that is absolutely needed for the absorption for Vitamin B-12
Where does most of the digestion and absorption of food occur in the GI tract?
The small intestine, which is approx 10 feet long
What is the shortest and longest section of the small intestine?
The shortest is the duodenum and the longest is the ileum
Where do the fat soluble nutrients go in the small intestine?
The fat soluble nutrients go into the lymph system, while the other nutrients are absorbed into the blood stream.
The liver produces _____________ which is stored in the __________ and enters the ____________ through the common bile duct. The bile begins to break down ____ into smaller pieces that can be mixed with water.
bile; gallbladder; duodenum; fat
Discuss the role of the pancreas....
The pancreas is an accessory digestive organ that releases pancreatic juice and hormones. The pancreatic juice is a mix of water, bicarbonate and enzymes that break down carbohydrates, protein and fats. The bicarbonate neutralizes the acidity of the chime to protect the intestinal wall. Without the bicarbonate, the high level of acid would destroy the lining leading to an ulcer. The hormones glucagon and insulin are also released to help with glucose regulation.
Where does undigested food go after the small intestine?
It passes through the ileocecal sphincter into the large intestine. The sphincter prevents the backflow of contents into the small intestine.
How are bacteria important to the large intestine?
Higher levels of good bacteria help to protect the body from disease causing bacteria and are an important part of the immune system. Bifidobacteria and lactobacilli are two types of bacteria that are considered important to our health. Some foods naturally contain these bacteria, while other food products have the bacteria added to them
What does it mean when a food is probiotic?
What does the term prebiotic mean?
Foods that naturally contain good bacteria such as Bifidobacteria and lactobacilli that are important to our gut health. Fermented milk and yogurt are two examples of probiotics that can be marketed to improve your gut health and digestion.
The term prebiotic refers to substances that stimulate bacterial growth in the large intestine.
Discuss the digestive disorder of Heartburn/acid reflux :
Symptoms, causes, Diagnosis treatments
Results from stomach acid coming up into the esophagus. The esophagus is not lined with mucus as the stomach is and the results is a burning sensation or pain, and it may cause nausea, coughing, gagging or hoarseness.
Primary cause is a weak and relaxed esophageal sphincter that does not fully prevent the backflow of the stomach contents into the esophagus.
If a person experiences heartburn several times per week they are diagnosed as having gastro-esophageal reflux or GERD.
Treatment in terms of diet include smaller meals that are low in fat, chewing foods well, avoiding overeating, and limiting intake of coffee, tea, alcohol and certain spices. In addition, it is often recommended to wait 2 hours after a meal before lying down and to sleep with the head of the bed elevated.
The result of dry, hard, infrequent stools. Slow movement of fecal material through the large intestine leads to this.
A change in diet and a review of medications can alleviate the problem. In the case of medications, calcium and iron are two of the most common causes of constipation. By making some dietary changes, bowel habits can become more frequent and regular. Eating high fiber foods such as whole grains, dried and fresh fruits and vegetables and nuts will stimulate the large intestinal muscles. Caution, as fiber is increased, the amount of liquids consumed should also increase. This will help to form a bulky, soft stool. Without the liquid, another issue, gas or flatulence will result.
Diarrhea is the opposite of constipation. It is characterized by loose, watery and frequent stools. Diarrhea usually results from an infection or a disease.
Treatment usually requires increased fluid consumption to prevent dehydration. A diet of broth, tea, toast and low fiber foods should be consumed as tolerated
What is diverticulosis?
Develops as we age- small pouches push out through weak spots in the colon and in the majority of people causes no problems.
At times though fod can get stuck in these pouches and result in inflammation or infection called diverticulitis.
A low fiber diet which causes straining to pass stools is the major cause of diverticulosis. Increasing your fiber intake may reduce the symptoms and prevent diverticulitis from developing.
What is irratable bowel syndrome?
More common in females than in males, this disorder is not well understood. It causes bloating, abdominal pain, cramps, diarrhea and or constipation.
Certain foods aggravate the symptoms: gas producing foods such as beans, milk products, alcohol, caffeine and fat. Therapy includes frequent small meals, low fat meals, high fiber intake, avoiding foods that trigger the symptoms, and probiotics.
Ulcers or peptic ulcer
The mucus lining of the stomach or small intestine erodes.
A bacteria, H. pylori, and nonsteroidal anti-inflammatory drugs (NSAID) erode the mucus lining. Stress, smoking and genetics also play a role in the development of an ulcer. Symptoms include a burning sensation in the stomach following a meal or at night, weight loss, nausea, vomiting and loss of appetite. Aside from avoiding foods that increase the symptoms, diet changes are not necessary. Treatment is based on lifestyle changes and medical treatment.