Question 1

Each is a function of saliva,except one.Which is the exception?

Accepted Answer

Saliva restores or returns calcium,phosphates,and other minerals into surfaces of teeth that have been damaged by caries,erosion,or abrasion.Saliva is supersaturated with calcium phosphates.

Question 2

Each is true of enzymes,except one.Which is the exception?

Accepted Answer

Enzymes enable metabolic reactions to proceed at a faster rate without being exhausted.Enzymes function similar to keys: they are highly specific and function on only one substrate,similar to a key fitting a particular lock.When the reaction is completed,the complex separates,releasing new chemical compounds and the enzyme.

Question 3

Digestion is accomplished solely through chemical activities on food because peristalsis permits blending of foodstuffs with digestive secretions.

Accepted Answer

The statement is not correct,but the reason is correct.Digestion involves two basic types of action on food: mechanical and chemical.Mechanical actions include chewing and peristalsis,both of which break up and mix foods.The mechanical actions permit better blending of foodstuffs with digestion secretions.

Question 4

Gluten sensitivity,an allergic condition,is an example of a systemic condition.Gluten-sensitive patients develop impairment of the small intestine.

Accepted Answer

Gluten sensitivity is an example of a systemic condition because it qualifies as a disease or disorder that affects the whole body,but it is not an allergic condition.Gluten-sensitive patients can develop gastrointestinal symptoms,but the small intestine is not impaired.Gluten is a protein composite found in foods processed from wheat.

Question 5

Saliva is supersaturated with bacterial by-products that allow demineralized areas of hydroxyapatite in enamel to be remineralized.Demineralization occurs when calcium,phosphate,and other minerals migrate from the enamel surface into the dentin.

Accepted Answer

Both statements are false.Saliva is supersaturated with calcium phosphates that allow demineralized areas of hydroxyapatite in enamel to be remineralized.Remineralization is defined as the restoration or return of calcium phosphates and other minerals into damaged tooth surfaces.Demineralization occurs when calcium,phosphate,and other minerals are lost from tooth enamel,causing tooth enamel to dissolve.

Question 6

Food-drug interactions have the potential to cause nutritional problems.For example,consuming milk or milk products while taking amoxicillin decreases the amount of antibiotic and calcium available to the body.

Accepted Answer

The first statement is true; the second is false.Amoxicillin undoubtedly has other food-drug interactions,but it is tetracycline that interacts with milk and milk products.The result of this interaction is that lowered amounts of tetracycline and calcium are available to the body.

Question 7

It is not uncommon for an elderly patient to state that food "just doesn't taste good," because the impairment of the olfactory nerves is prevalent in older adults.

Accepted Answer

Both the statement and the reason are correct and related.Aromas stimulate olfactory nerves,which are receptors for smell.Prevalence of impairment of olfactory nerves is high in older adults,with the problem increasing with age.

Question 8

During peristalsis,doorlike mechanisms called valves or sphincter muscles perform all of the following functions,except one.Which is the exception?

Accepted Answer

Valves or sphincter muscles within the alimentary tract are strictly involved in mechanical aspects of digestion and do not synthesize dietary enzymes.An example of valvular peristaltic action is the small amounts of chyme that are released from the stomach through the pyloric sphincter to allow for adequate digestion and absorption in the small intestine.Regulation of these valves is complex,involving muscular function and different pressures on each side of the valve.

Question 9

Mechanical aspects of digestion include chewing and hypergeusia.Mechanical actions involve peristalsis,voluntary waves of contraction traveling the whole length of the alimentary tract.

Accepted Answer

Both statements are false.Mechanical aspects of digestion include chewing and peristalsis.Peristalsis is a series of involuntary,not voluntary,rhythmic waves of contraction traveling the whole length of the alimentary tract.Note that hypergeusia is a condition where the sense of taste is heightened.

Question 10

Taste buds,receptors of taste located in the oral cavity,play an important role in the digestive system.Visual sensory perceptions associated with the presentation and color of food are known as gustatory sensations.

Accepted Answer

The first statement is true; the second is false.Gustatory refers to taste,which is one of the three sensory perceptions that influence food choices.The remaining two are sight and smell.As food is chewed,gustatory receptors are exposed to chemicals dissolved in saliva.

Question 11

The maxilla and mandible need the forces of chewing to prevent calcium absorption.Chewing firm food helps to maintain a proper balance between bone breakdown and new bone formation within the alveolar process.

Accepted Answer

The first statement is false; the second is true.The maxilla and mandible need chewing forces to prevent the resorption,not absorption,of calcium.Resorption breaks down a substance; absorption integrates a substance into the body.Calcium absorption is a desired process,whereas calcium resorption is not.The alveolar process is the crest of the maxilla and mandible that serves as the bony investment for the teeth.

Question 12

The small intestine is comprised of the cecum,colon,and rectum.The large intestine includes the duodenum,jejunum,and ileum.

Accepted Answer

Both statements are false.The statements are reversed.The small intestine is comprised of the duodenum,jejunum,and ileum.The large intestine includes the cecum,colon,and rectum.

Question 13

Gustatory and olfactory disorders can result in the deterioration of a patient's general condition or nutritional status.Potentially adverse compensatory habits can contribute to dental caries and systemic conditions.

Accepted Answer

Both the statement and the reason are correct and related.It is not unusual for patients with impaired taste (gustatory)and smell (olfactory)senses to decline in health.In an effort to enjoy meals,many patients make compensatory changes such as adding of sugar and other sweeteners.These substances have detrimental health consequences,including dental caries and blood glucose disturbances.The addition of salt,another compensatory measure to improve the eating experience,negatively affects cardiovascular health.

Question 14

Each is a portion of the alimentary canal,except one.Which is the exception?

Accepted Answer

The larynx is not a portion of the alimentary canal.This tubular structure is approximately 30-ft long and comprises all the body parts through which food passes.

Question 15

The use of over-the-counter enzyme tablets might not be beneficial to patients because the enzymes within the product are digested before they can be used.

Accepted Answer

Both the statement and the reason are correct and related.Prescription enzymes are more likely to have protective features which prevent the active ingredient from being digested prior to the point at which it can be used.For example,prescription pancreatic enzymes have a special enteric coating preventing the enzyme from exposure to gastric juices.An example of an OTC product that has such a protective feature is lactase which is effective for lactose intolerant because it is either added to or taken with lactose-containing foods.

Question 16

Demineralization is a result of acids produced by fermentable carbohydrates combining with proteins to form prebiotics.Demineralization is caused by a lack of calcium intake or a calcium deficiency.

Accepted Answer

Both statements are false.Demineralization is a result of acids produced by fermentable carbohydrates combining with acidogenic bacteria.It is not caused by lack of calcium intake or a calcium deficiency.Note that prebiotics are nondigestible food ingredients that have beneficial effects within the large intestine and colon.

Question 17

Hydrolysis of a starch begins with which enzyme?

Accepted Answer

Some chemical action or hydrolysis of nutrients begins in the mouth.Salivary amylase initiates starch digestion.If a carbohydrate,such as a cracker,is chewed and held in the mouth for a few seconds,it will begin to taste sweet.This denotes that some of the starch is being hydrolyzed to dextrin and maltose.Note that the name for many enzymes is derived from the name of its substrate,with the suffix -ase.Sucrase is the enzyme that hydrolyzes sucrose.

Question 18

Loss of smell results in a condition that limits capacity to detect flavor of food and beverages called:

Accepted Answer

Anosmia,or loss of smell,results in limited capacity to detect flavor of food and beverage.Upper respiratory infections,nasal or sinus problems,and neurological disorders can cause anosmia.Hypergeusia is heightened taste acuity.Dysgeusia is persistent,abnormal distortion of taste.Phantom taste is dysgeusia without identifiable taste stimuli.Peristalsis is a mechanical action involved in digestion.It involves involuntary rhythmic waves of contraction in the alimentary tract.

Question 19

The accessory organs include the large and small intestines.The role of accessory organs is to store foodstuffs during the digestive process.

Accepted Answer

Both statements are false.The accessory organs are the salivary gland,liver,gallbladder,and pancreas.They provide secretions essential for digestion and absorption.

Question 20

Each descriptions of taste papillae is true,except one.Which is the exception?

Accepted Answer

Taste papillae appear on the tongue as little,not large,red dots,or raised bumps.They are most numerous on the dorsal surface of the tongue,which is the top surface.Disease,drugs,nutritional status,radiation,and age can affect taste papillae.

Quiz 3: The Alimentary Canal: Digestion and Absorption