Question 1

The capillaries that nourish the epithelium and absorb digested nutrients lie in the ________.

Accepted Answer

The lamina propria contains capillaries that nourish the epithelium and absorb digested nutrients. The adventitia, submucosa, and serosa are all layers found outside of the mucosa layer.

Question 2

Select the statement that is true concerning primary teeth.

Accepted Answer

Primary teeth, also known as baby teeth, consist of 20 teeth which usually erupt by the age of 24 months. Option B is incorrect as there are no permanent teeth among the primary teeth. Option C is incorrect as there are only 20 primary teeth instead of 32. Option D is incorrect as the eruption of primary teeth continues up to 33 months and no new primary teeth appear after that.

Question 3

Select the one response below that would not result from a drug that blocks histamine receptors in the cells lining the stomach.

Accepted Answer

Blocking histamine receptors in the cells lining the stomach would reduce the activity of parietal cells, which produce acid. This would result in reduced symptoms of heartburn (A) and higher pH of the stomach (D). However, it would not cause the release of secretin and cholecystokinin (B), which are hormones released in response to the presence of acidic chyme in the duodenum, not in response to histamine receptors in the stomach lining.

Question 4

The mechanical and chemical receptors that control digestive activity are located ________.

Accepted Answer

Mechanical and chemical receptors that control digestive activity are located in the walls of the tract organs, such as the stomach, small intestine, and large intestine. These receptors respond to stretch, contraction, and pH changes to regulate digestive secretions and contractions. Glandular tissue and the oral cavity also play important roles in digestion but they do not have receptors that directly control digestive activity. The pons and medulla are part of the nervous system that regulates digestive functions but they are not actually located in the digestive tract.

Question 5

When we ingest large molecules such as lipids,carbohydrates,and proteins,they must undergo catabolic reactions whereby enzymes split these molecules.This series of reactions is called ________.

Accepted Answer

Chemical digestion refers to the breakdown of large molecules into smaller molecules through enzymatic reactions. This process occurs in the digestive system and is required to extract nutrients from food. Mechanical breakdown refers to the physical process of breaking down food into smaller pieces through chewing, grinding, and mixing. Absorption refers to the process of nutrients passing through the lining of the small intestine into the bloodstream. Secretion refers to the release of digestive enzymes and other substances into the digestive tract to aid in digestion.

Question 6

The sight of food can trigger a series of events that results in the release of gastric juice.All but one of the following is true in regards to the previous statement.Select the one answer that is not true.

Accepted Answer

The motor nerves of the pathway triggered by the sight of food are actually part of the parasympathetic division of the autonomic nervous system, not the sympathetic division.

Question 7

Some antacid drugs block histamine receptors,resulting in reduction of the production and excretion of stomach acid.These drugs have the biggest effect on which of the following?

Accepted Answer

Parietal cells are responsible for the production and excretion of stomach acid. Blocking histamine receptors on these cells would result in a reduction of acid production and secretion.

Question 8

Choose the incorrect statement regarding bile.

Accepted Answer

Bile does not contain enzymes for digestion. It helps in the process of digestion by emulsifying fats, but does not have digestive enzymes.

Question 9

From the esophagus to the anal canal,the walls of every organ of the alimentary canal are made up of the same four basic layers.Arrange them in order from the lumen.

Accepted Answer

The order from the lumen of the alimentary canal is mucosa, submucosa, muscularis externa, and serosa. This order allows for absorption and movement of the contents of the canal. The mucosa is the innermost layer that comes into contact with the food, and it contains epithelial cells and some connective tissue. The submucosa is a layer of connective tissue that contains blood vessels, lymphatics, and nerves. The muscularis externa is responsible for the movement of the food through the canal and has two layers of smooth muscle. The serosa is the outermost layer that provides protection and support.

Question 10

The absorptive effectiveness of the small intestine is enhanced by increasing the surface area of the mucosal lining.Which of the following accomplish this task?

Accepted Answer

Villi and microvilli increase the surface area of the mucosal lining, allowing for more efficient absorption of nutrients from digested food.

Question 11

The function of the hepatic portal circulation is to ________.

Accepted Answer

The hepatic portal circulation collects absorbed nutrients from the digestive system and carries them to the liver for metabolic processing before they are released into the general circulation. This includes nutrients like glucose, amino acids, and fatty acids. The hepatic portal circulation does not deal with toxins or hormones specifically.

Question 12

Generally the hormones secretin and cholecystokinin which are released by duodenal enteroendocrine cells will ________.

Accepted Answer

Secretin and cholecystokinin are released by duodenal enteroendocrine cells in response to the presence of acidic chyme in the small intestine. These hormones help to slow down the activities of the stomach in order to prevent the small intestine from being overwhelmed with too much chyme at once. Secretin also stimulates the release of bicarbonate from the pancreas, which helps to neutralize the acidic chyme entering the small intestine.

Question 13

What part of the tooth bears the force and resists the friction of chewing?

Accepted Answer

Enamel is the hard, outermost layer of the tooth that covers the crown. It is the hardest substance in the body and is designed to withstand the force and friction of chewing.

Question 14

The chemical and mechanical processes of food breakdown are called ________.

Accepted Answer

The chemical and mechanical processes of food breakdown are referred to as digestion. Secretion refers to the release of substances, such as hormones or enzymes, from specific organs or glands in the body. Ingestion refers to the act of taking in food or drink. Absorption refers to the movement of nutrients or other substances through the walls of the intestine and into the bloodstream.

Question 15

Which of the following is not a factor that helps create the stomach mucosal barrier?

Accepted Answer

Secretion of pepsinogen is not a factor that helps create the stomach mucosal barrier. Pepsinogen is actually an enzyme precursor that is converted to the active enzyme, pepsin, which aids in protein digestion. The other options (A, B, and D) are factors that do help create the stomach mucosal barrier.

Question 16

Proteins entering the stomach act as a buffer raising pH.Rising pH stimulates the activity of G-cells in the lining of the stomach.All of the following but one will occur.Select the statement below that would not occur.

Accepted Answer

Positive feedback response would not occur as it would lead to uncontrollable and potentially harmful levels of acid production. The pH buffer system and G-cell stimulation help to maintain a controlled and balanced acidity level in the stomach.

Question 17

In the enteric nervous system,a long reflexive pathway has an advantage over a short reflexive pathway in the fact that ________.

Accepted Answer

Long reflexive pathways involve the central nervous system and can be stimulated by external factors such as the sight, smell, or thought of food, unlike short reflexive pathways that are localized within the enteric nervous system of the GI tract.

Question 18

All of the following are true of swallowing (deglutition)except one.Select the statement that is not true of swallowing.

Accepted Answer

The epiglottis is a flap of cartilage that prevents food or liquids from entering the trachea during swallowing. It does not assist in propelling food into the trachea, which would be dangerous and could lead to choking or aspiration pneumonia.

Question 19

Generally the hormones secretin and cholecystokinin which are released by duodenal enteroendocrine cells will ________.

Accepted Answer

Secretin and cholecystokinin stimulate the pancreas to release digestive enzymes and also stimulate the gallbladder to release bile, thus increasing the release of digestive enzymes and bile. They do not decrease the activities of the accessory digestive organs or increase stomach emptying or the force of stomach contractions.

Question 20

The sheets of peritoneal membrane that hold the digestive tract in place are called ________.

Accepted Answer

Mesenteries are sheets of peritoneal membrane that hold the digestive tract in place. Mucosal lining and lamina propria are layers within the digestive tract, and the serosal lining is the outer layer of the peritoneum.

Quiz 23: The Digestive System

The capillaries that nourish the epithelium and absorb digested nutrients lie in the ________.

Select the statement that is true concerning primary teeth.

Select the one response below that would not result from a drug that blocks histamine receptors in the cells lining the stomach.

The mechanical and chemical receptors that control digestive activity are located ________.

When we ingest large molecules such as lipids,carbohydrates,and proteins,they must undergo catabolic reactions whereby enzymes split these molecules.This series of reactions is called ________.

The sight of food can trigger a series of events that results in the release of gastric juice.All but one of the following is true in regards to the previous statement.Select the one answer that is not true.

Some antacid drugs block histamine receptors,resulting in reduction of the production and excretion of stomach acid.These drugs have the biggest effect on which of the following?

Choose the incorrect statement regarding bile.

From the esophagus to the anal canal,the walls of every organ of the alimentary canal are made up of the same four basic layers.Arrange them in order from the lumen.

The absorptive effectiveness of the small intestine is enhanced by increasing the surface area of the mucosal lining.Which of the following accomplish this task?

The function of the hepatic portal circulation is to ________.

Generally the hormones secretin and cholecystokinin which are released by duodenal enteroendocrine cells will ________.

What part of the tooth bears the force and resists the friction of chewing?

The chemical and mechanical processes of food breakdown are called ________.

Which of the following is not a factor that helps create the stomach mucosal barrier?

Proteins entering the stomach act as a buffer raising pH.Rising pH stimulates the activity of G-cells in the lining of the stomach.All of the following but one will occur.Select the statement below that would not occur.

In the enteric nervous system,a long reflexive pathway has an advantage over a short reflexive pathway in the fact that ________.

All of the following are true of swallowing (deglutition) except one.Select the statement that is not true of swallowing.

Generally the hormones secretin and cholecystokinin which are released by duodenal enteroendocrine cells will ________.

The sheets of peritoneal membrane that hold the digestive tract in place are called ________.