The small and large intestines are composed of several segments. They are present in the following sequence:
A) duodenum, jejunum, ileum, colon, rectum
Distinguish between mechanical and chemical digestion
Mechanical digestion is the breakdown of foods by the action of the teeth and muscles. It results in the production of food particles mixed with and suspended in fluid.
Chemical digestion is the breakdown of foods by digestive enzymes into basic units that can be absorbed and used by the body
Distinguish between peristalysis and segentation
Peristalsis is a form of muscular propulsion that results from the alternating contraction of the circular and longitudinal muscles of the GI tract. The result is a wavelike movement that forces the food along the tract
Segmentation is a periodic squeezing of the circular muscles that results in mixing of the intestinal contents; it also increases contact of intestinal contents with the intestinal wall
What are the physical characteristics of chyme, and why is it important in the digestive process?
Chyme is a semi-liquid mixture of tiny food particles produced in the stomach and expelled into the duodenum. The physical characteristics of chyme allow the digestive enzymes greater access to the food particles.
__________is not a form of mechanical digestion
B) Bacterial fermentation in the large intestine
The breakdown of nutrients into basic absorbable units is accomplised through _________ digestion
-Chemical
In the digestion of food, the role of the stomach is to
D) start the digestion of protein and fat
The function of mucus in the stomach is to
B) protect the stomach wall from being digested by gastic juice
Explain the importance of hydrochloric acid in the stomach?
Hydrochloric acid prevents bacterial growth and kills most bacteria in the stomach. It also catalyzes the process by which proteins are broken down into usable units
Of the functions listed below, only__________is not performed by bacteria in the intestine
A) producing a variety of minerals
The villi and microvilli of the small intestine
B) a, b, and c
The lymphatic system is responsible for the absorption of __________from the small intestine
D) fats and fat-soluble vitamins
Of the products of digestion listed below,__________do/does not have direct access to the bloodstream
D) long-chain fatty acids
Blood leaving the digestive system goes to the _______
-liver
When someone appears to be choking, the first thing to do is to
A) ask the person to make a sound
What is constipation? Discuss the different ways of preventing it
Constipation, a condition in which bowel movement is difficult, is associated with discomfort and pain caused by the hard texture of the stools. Several ways of preventing constipation are to
- respond to the defecation signal
-include prune juice, which contains a natural laxative substance, in the diet
-increase dietary fibre (eg. wheat bran, vegetables, and grains)
-increase fluid intake
-increase physical activity
Of the factors listed below,_________is/are not a major cause of ulcers