Question 1

Eating large amounts of acidic fruits such as limes and grapefruit may have this impact on the body.

Accepted Answer

Eating large amounts of acidic fruits such as limes and grapefruit may cause enamel damage to teeth due to the erosion of the protective layer of enamel.

Question 2

Pepsinogen is converted to pepsin by the presence of what other substance?

Accepted Answer

Pepsinogen is converted to pepsin by the presence of hydrochloric acid (HCl) in the stomach.

Question 3

This digestive organ absorbs water from indigestible food residue, stores feces, and eliminates feces from the body.

Accepted Answer

The large intestine is responsible for the absorption of water from indigestible food residue, storing feces, and eliminating feces from the body. The rectum is a part of the large intestine where feces are stored before elimination. The small intestine is responsible for the absorption of nutrients, while the stomach is responsible for the initial digestion of food.

Question 4

This enzyme will break down starch into smaller subunits.

Accepted Answer

Amylase is an enzyme that breaks down starch into smaller subunits such as maltose and glucose. Pepsin is a protease enzyme that breaks down proteins in the stomach, lipase breaks down lipids, and renin is an enzyme involved in the digestion of milk proteins.

Question 5

The following products diffuse into the lacteal.

Accepted Answer

Triglycerides are broken down into fatty acids and glycerol by lipase enzymes and are then absorbed into the lacteal, where they form chylomicrons and are transported through the lymphatic system. Monosaccharides, ions, and amino acids are absorbed into the bloodstream through capillaries in the intestinal wall.

Question 6

Erosion of the gastrointestinal tract that results in a sore is called a ________.

Accepted Answer

Peptic ulcer is the term used to describe the erosion of the gastrointestinal tract that results in a sore. A pore is a small opening in the skin, while a chancre is a sore associated with syphilis. A diverticulum is a small pouch that bulges outward from the lining of the colon.

Question 7

Which of the following is a J-shaped muscular sac that serves in the temporary storage of masticated food while digestive enzymes and HCl are released to digest proteins?

Accepted Answer

The J-shaped muscular sac that stores masticated food while digestive enzymes and HCl are released to digest proteins is the stomach. The large intestines and colon are involved in absorbing water and electrolytes from remaining food material, while the esophagus is the muscular tube that transports food from the mouth to the stomach.

Question 8

Which of these events occurs normally in swallowing?

Accepted Answer

The larynx rises during swallowing to assist in closing the trachea, ensuring that food or liquid is directed towards the esophagus and not the airway.

Question 9

This pancreatic enzyme breaks triglycerides into glycerol and fatty acids.

Accepted Answer

Lipase is the pancreatic enzyme that breaks down triglycerides into glycerol and fatty acids. Maltase breaks down maltose (a disaccharide), trypsin breaks down proteins, and carboxypeptidase breaks down peptides.

Question 10

A PillCam traveling from the pharynx to the stomach will first pass through the ________.

Accepted Answer

The esophagus is the muscular tube that connects the pharynx to the stomach, making it the correct answer. The tonsil and uvula are part of the oral cavity and not part of the digestive tract. The sphincter is a muscular valve that regulates the movement of food in and out of the stomach, but it is not the first structure that the PillCam would pass through on its journey from the pharynx to the stomach.

Question 11

These sharply pointed teeth on the sides of the mouth tear food.

Accepted Answer

Canines are the teeth that are designed to tear food with their sharply pointed edges. Incisors are the front teeth that are used for cutting and biting, premolars are used for grinding and crushing, while molars are used for grinding and chewing.

Question 12

Infection with Helicobacter pylori can cause ________.

Accepted Answer

Infection with Helicobacter pylori commonly causes peptic ulcers, which are painful sores that develop in the lining of the stomach or small intestine.

Question 13

If a person were unable to produce much of this substance, the gastric juices might destroy the stomach lining.

Accepted Answer

Mucus is a thick, sticky substance that lines the stomach and protects it from the corrosive effects of gastric juices, particularly HCl. If a person is unable to produce sufficient mucus, the stomach lining may be susceptible to damage from the HCl in gastric juice. Chyme refers to the partially digested food mixture that moves from the stomach to the small intestine. HCl is a component of gastric juice that helps to break down food and kill bacteria. Pepsin is an enzyme produced in the stomach that helps to digest proteins.

Question 14

The stomach begins chemical digestion of which of these substances?

Accepted Answer

The stomach begins chemical digestion of proteins with the help of hydrochloric acid, which denatures the proteins and converts pepsinogen to pepsin, an enzyme that breaks down proteins into smaller peptides.

Question 15

A passageway shared by the digestive and respiratory systems is the ________.

Accepted Answer

The pharynx is a shared passageway for both the digestive and respiratory systems; it connects the nose and mouth to the esophagus and trachea. The larynx is part of the respiratory system and contains the vocal cords. The sinuses are air-filled spaces in the skull that are connected to the nasal cavity. The esophagus is a muscular tube that connects the pharynx to the stomach and is part of the digestive system.

Question 16

Chyme travels from the stomach to which specific structure?

Accepted Answer

Chyme travels from the stomach to the duodenum, which is the first part of the small intestine.

Question 17

Adding ________ to municipal water supplies will reduce the rate of tooth decay.

Accepted Answer

Adding fluoride to municipal water supplies has been shown to reduce the rate of tooth decay, as it helps strengthen tooth enamel and prevent cavities. Chloride, peroxide, and aldehyde are not effective for this purpose.

Question 18

Which of the following is a common ailment characterized by a burning sensation caused by gastric juices backing up into the esophagus?

Accepted Answer

Heartburn is a common ailment characterized by a burning sensation in the chest area caused by gastric juices backing up into the esophagus. Acidosis is a condition caused by an increase in acidity in the blood, porosis is not a medical term and gastritic stress is not a commonly used medical term.

Question 19

If a gallstone were to block the bile duct, which type of food would become more difficult to digest?

Accepted Answer

If a gallstone blocks the bile duct, the flow of bile from the liver to the small intestine is obstructed, leading to impaired fat digestion. The other types of food mentioned (protein, sugar, starch) are not primarily digested by bile but by other digestive enzymes, and thus would not be as affected by a blocked bile duct.

Question 20

The innermost lining of the gastrointestinal tract is the ________.

Accepted Answer

The mucosa is the innermost lining of the gastrointestinal tract, which is responsible for secreting mucus and digestive enzymes. It also contains glands that produce hormones and produces intestinal villi that help in nutrient absorption. The other options, serosa, muscularis, and submucosa, are layers surrounding the mucosa but are not the innermost lining.

Quiz 20: The Digestive System and Nutrition