Digestive System

The submucosa is a layer of the gastrointestinal tract that contains connective tissue, nerves, blood and lymph vessels, and smooth muscle. True False

False (lack smooth muscles)

Why is it possible to swallow while standing on one's hands? a. Peristalsis pushes food along the digestive tract in the right direction. b. Bacteria clog the digestive tube and prevent food from moving in the wrong direction. c. A wave of muscle contraction called emulsification prevents food from moving backward. d. Valves in the digestive system keep food from moving backward.

a

_________ is a hormone produced by the small intestine that causes the gallbladder to contract and release bile. a. cholecystokinin b. vasoactive intestinal peptide c. secretin d. gastrin

a

__________ is a liquid mixture of food and gastric juices found in the stomach. a. Chyme b. Saliva c. Bolus d. Bile

a

Where does protein digestion begin? a. small intestine b. stomach c. mouth d. esophagus

b

Which of the following is a common ailment characterized by a burning sensation caused by gastric juices backing up into the esophagus? a. gastritic stress b. heartburn c. porosis d. acidosis

b

________ cancer is the second-leading cause of cancer deaths, but early detection by using a long, flexible fiber tube to screen for precancerous polyps can save many lives. a. Gastric b. Colorectal c. Liver d. Lung

b

The absorption of the majority of ingested nutrients takes place largely in the __________. a. mouth b. small intestine c. stomach d. large intestine

b The villi, microvilli, and tubular glands called the crypts in the small intestine provide a large surface area through which the body absorbs nutrients.

A hormone released in the small intestine that stimulates the pancreas to release digestive enzymes and the gallbladder to release bile is known as ________. a. gastrin b. secretin c. cholecystokinin d. vasoactive intestinal peptide

c

After a meal of greasy fries, which of the following digestive secretions would you expect to be most active? a. salivary amylase b. HCl c. bile and lipase d. pepsin

c

Beneficial bacteria that synthesize vitamin K and some of the B vitamins are an important part of our digestion. The part of the digestive system where these bacteria are found is the ________ a. appendix b. stomach c. colon d. rectum

c

Chyme travels from the stomach to which specific structure? a. large intestine b. pancreas c. duodenum d. jejunum

c

If a person were unable to produce much of this substance, the gastric juices might destroy the stomach lining. a. pepsin b. chyme c. mucus d. HCl

c

One of the main jobs of stomach acid and bile is to __________ a. chemically digest food b. act as digestive enzymes c. separate connective and fatty tissues in food d. pull apart the covalent bonds in food molecules to make the molecules smaller

c

Pepsinogen is converted to pepsin by the presence of what other substance? a. intrinsic factor b. mucus c. HCl d. vitamin B12

c

Starch is a type of _____. a. disaccharide b. nucleotide c. polysaccharide d. fatty acid e. monosaccharide

c

The absorption mechanism that requires a specific carrier molecule, but no energy, to move digested nutrients across the cell membrane is called __________. a. carrier absorption b. simple diffusion c. facilitated diffusion d. active transport

c

The innermost lining of the gastrointestinal tract is the ________. a. serosa b. muscularis c. mucosa d. submucosa

c

The tongue functions to __________. a. grind and crush the food b. protect the opening of the pharynx during swallowing c. position food for swallowing d. add moisture and enzymes to the food

c

This pancreatic enzyme breaks triglycerides into glycerol and fatty acids. a. maltase b. carboxypeptidase c. lipase d. trypsin

c

What is primarily the role of the bacteria found in the large intestine? a. to cause disease b. to provide a natural source of protein c. to help digest food and produce vitamins d. to absorb critical vitamins

c

What is the longest part of the gastrointestinal tract? a. large intestine b. stomach c. small intestine d. esophagus

c

Which of these events occurs normally in swallowing? a. The epiglottis rises. b. The bolus rises. c. The larynx rises. d. The esophagus closes.

c

Triglycerides initially travel in the bloodstream away from the small intestine in ________ of the lymphatic system.

lacteals

A mascular tube that absorbs water and some nutrients and stores waste material.

large intestine

Which of the following hormones directly causes the release of sodium bicarbonate, which leads to thesecretions neutralization ofes acidic chyme from the stomach? a. Secretin b. Gastrin c. Vasoactive intestinal peptide d. Cholecystokinin

a

An opening at one end of the gastrointestinal tract that functions in mechanical digestion and the breakdown of carbohydrates by secreting amylase.

mouth

What is the most important function of the stomach? a. storage of food b. absorption of nutrients c. chemical digestion d. mucus secretion

b

Where does chemical digestion of food begin? a. stomach b. mouth c. liver d. small intestine

b

Peristalsis occurs only in the esophagus. True False

F Peristalsis is a wave of involuntary contractions that push food throughout the gastrointestinal tract.

Small fat-soluble molecules, such as free fatty acids and fat-soluble vitamins, are absorbed through facilitated diffusion in the small intestine. True False

F simple diffusion

Alcohol is considered an essential nutrient. true false

F

Approximately 66 percent of our body water is found in the extracellular fluid. True False

F

Teeth, much like bone, are dead. True False

F

The liver breaks down and metabolizes alcohol at a rate of about 1 ounce per hour. true false

F

The mouth is involved only in mechanical breakdown of food. True False

F

Absorption of protein and carbohydrates begins in the stomach. True False

F (digest in stomach but absorb in small intestine)

A capillary bed is located in the center of each villus and transports ions, water, and the products of protein and carbohydrate digestion directly to the rest of the body. True False

T

Amino acids are absorbed through the process known as active transport. True False

T

Gallstones consist of cholesterol that has precipitated from bile during storage in the gallbladder. True False

T

Heartburn does NOT involve the heart at all. True False

T

Jaundice is due to a buildup of bilirubin within the bloodstream. True False

T

The brown color of feces is due to bile pigments. True False

T

The pharynx is shared by the digestive and respiratory systems. True False

T

The presence of fatty acids and amino acids in the stomach contents triggers the small intestine to secrete a hormone known as _____. a. cholecystokinin, or CCK b. histones c. insulin d. secretin e. thyroxine

a

A passageway shared by the digestive and respiratory systems is the ________. a. pharynx b. sinuses c. esophagus d. larynx

a

Bile is produced by the _____ and stored by the _____ until it is secreted into the small intestine. a. liver ... gall bladder b. pancreas ... gall bladder c. liver ... pancreas d. gall bladder ... liveresophagus ... stomach

a

Chemical digestion __________. a. occurs when enzymes break apart large molecules into smaller molecules b. begins in the mouth with the process known as mastication c. occurs in the small intestine with the process known as segmentation d. occurs through the process known as peristalsis

a

Chemical digestion of fats first occurs in the __________. a. small intestine b. mouth c. large intestine d. stomach

a

Saliva contains an enzyme that begins the chemical digestion of __________. a. starch b. fats c. nucleic acids d. proteins

a

Secretin stimulates the _____ to secrete _____. a. pancreas ... bicarbonate b. pancreas ... pancreatic enzymes c. small intestine ... disaccharidases d. stomach ... bicarbonate

a

What acid is responsible for stomach acidity? a. hydrochloric acid b. carbonic acid c. sulfuric acid d. acetic acid e. sodium hydroxide

a

Severe pain in the lower right abdomen along with fever and nausea is often a sign of an infection in this structure.

appendix

Adding ________ to municipal water supplies will reduce the rate of tooth decay. a. peroxide b. fluoride c. aldehyde d. chloride

b

Cholecystokinin (CCK) stimulates the _____ to secrete _____. a. pancreas ... bicarbonate b. pancreas ... pancreatic enzymes c. small intestine ... disaccharidases d. stomach ... bicarbonateliver ... liver enzymes

b

Erosion of the gastrointestinal tract that results in a sore is called a ________. a. pore b. peptic ulcer c. chancre d. diverticulum

b

Infection with Helicobacter pylori can cause ________. a. constipation b. peptic ulcers d. tooth decay e. gallstones

b

The __________ is the organ that produces bile. a. stomach b. liver c. salivary glands d. pancreas

b

The fingerlike projections along the surface of the small intestine are called __________. a. circular folds b. villi c. lacteals d. capillaries

b

The following products diffuse into the lacteal: a. monosaccharides b. triglycerides c. amino acids d. ions

b

The hormone gastrin is released by the stomach. Its function is to stimulate the release of gastric juices. What is the stimulus to release this hormone? a. the aroma of food b. the distension of the stomach and presence of protein c. the sight of food d. the process of chewing food

b

The type of inflammation of the gum in which bacteria grow in pockets between the gums and the teeth and in which teeth may become loose is called ________. a. caries b. periodontitis c. gingivitis d. pulpitis

b

These sharply pointed teeth on the sides of the mouth tear food. a. incisors b. canines c. molars d. premolars

b

What is the function of bile? a. Bile is first produced in the gallbladder. b. Bile aids in the digestion of fats by emulsifying fats. c. Bile helps dissolve gallstones. d. Bile causes several serious diseases of the liver.

b

You are a pediatrician. A woman brings in her 1-year-old son, who has severe diarrhea. You prescribe an antidiarrhea medicine, which __________. a. speeds up peristalsis in the large intestine b. speeds up peristalsis in the small intestine c. increases the amount of water absorbed from the large intestine d. kills all bacteria in the large intestine

c

A muscle located at the end of the esophagus must relax before the bolus can enter the stomach. This muscle is called the __________. a. ileocecal valve b. cecum c. gastroesophageal or lower esophageal sphincter d. pyloric sphincter

c As the bolus nears the end of the esophagus, a muscle called the gastroesophageal or lower esophageal sphincter relaxes to allow the food into the stomach. The pyloric sphincter is located between the stomach and the duodenum. Undigested or unabsorbed nutrients and other compounds from food enter the large intestine through the ileocecal valve. As the waste material enters the cecum, it mixes with intestinal bacteria, which digest any remaining particles.

Protein digestion begins in the _____. a. mouth b. esophagus c. stomach d. small intestine e. large intestine

c The secretion of gastric juice by the stomach begins the digestion of proteins.

Your small intestine can absorb ____ without their being further digested. a. starches b. fats c. proteins d. fructoses e. nucleic acids

d Fructose is a monosaccharide, and monosaccharides can be absorbed without having to be broken down into smaller units.

Which of these enzymes begins the breakdown of starch? a. bile b. disaccharidases c. lipase d. amylase e. nucleases

d The digestion of starches, such as amylose, begins with the amylase secreted by the salivary glands.

Samantha drank a loot of alcohol over many years and now suffers from this fatty degeneration of the liver.

corrhosis

If a person were born with the inability to produce pepsin, how would this affect his or her digestion? a. He or she would fail to metabolize glucose. b. He or she could not break down lactose. c. He or she would no longer be able to absorb DNA. d. He or she would digest proteins with difficulty.

d

John consumed a large margarita that contained 14 grams of carbohydrate and 24 grams of alcohol. How many kilocalories did he consume? a. 152 kilocalories b. 168 kilocalories c. 200 kilocalories d. 224 kilocalories

d

The acidity of the stomach contents triggers the small intestine to secrete a hormone known as _____. a. cholecystokinin, or CCK b. histones c. TSH d. secretin e. pepsin

d

The main area of absorption in your digestive system is found in the __________. a. large intestine b. colon c. stomach d. small intestine

d

The stomach begins chemical digestion of which of these substances? a. carbohydrates b. fats c. sugars d. proteins

d

The villi in the wall of the small intestine function to __________. a. help mix the food with digestive enzymes b. secrete digestive enzymes c. secrete bile d. increase the surface area for absorption

d

This enzyme will break down starch into smaller subunits. a. lipase b. pepsin c. renin d. amylase

d

What is the main component of gastric juice? a. inactive pepsin b. amylase c. hydrochloric acid d. water e. bile

d

What is the primary function of the digestive system? a. chemical breakdown of food using enzymes b. chewing of food to mechanically break it down c. acidification of food d. chemical and mechanical breakdown of food

d

When digested, proteins are broken down into _____. a. glycerol only b. fatty acids only c. monosaccharides d. amino acids e. both glycerol and fatty acids

d

Which of the following choices most completely describes the functions of water in the body? a. digestion b. transporting nutrients c. protection and lubrication d. Water is essential for all of these functions.

d

Which of the following describe(s) how to keep teeth and gums healthy? a. Avoid sticky foods.Brush your teeth twice a day and floss regularly. b. Choose a diet low in sugar. c. Use fluoridated toothpaste or get fluoride treatments from your dentist. d. All of the listed responses describe good dental practices.

d

Which of the following is NOT a function of saliva? a. helps clean the mouth b. begins the chemical breakdown of starches c. moistens food and helps stick it together to make it easier to swallow d. contains fluoride to harden the tooth enamel

d

Which of the following statements about alcohol is correct? a. Alcohol does not need to be digested before it can be absorbed. b. On an empty stomach, alcohol can be absorbed through the lining of the stomach. c. Women absorb about one-third more alcohol than men because women have fewer stomach enzymes that break down the alcohol prior to absorption. d. All of these statements about alcohol are true.

d

You are a pediatrician. A woman brings in her 1-year-old son, who has severe diarrhea. You would be most immediately concerned about the child's loss of __________ due to the diarrhea. a. fiber b. protein c. fat d. water

d

You go out with your friends to celebrate your birthday and share a sausage pizza. Where does the digestion of the oil BEGIN? a. in the esophagus b. in the small intestine c. in the stomach d. in the mouth

d

Food that has been moistened with saliva and then swallowed through the esophagus is called __________. a. chyme b. an epiglottis c. pepsin d. a bolus

d Food that is moistened with saliva is called a bolus. The bolus moves to the back of the mouth, and the brain temporarily closes the epiglottis to prevent the bolus from entering the trachea. The soft palate also rises to seal off the nasal passages to prevent aspiration of food or liquid into the sinuses. As the trachea closes, the esophagus opens, allowing the bolus to be swallowed into the esophagus to the stomach by way of muscular contractions called peristalsis.

Which of the following statement(s) regarding digestion is/are correct? a. Mechanical digestion in the stomach mixes and churns the bolus until it becomes a liquid called chyme. b. The presence of chyme in the duodenum stimulates the gallbladder and the pancreas to release bile and pancreatic juice. c. The gallbladder secretes bile, which emulsifies the fat, breaking it into smaller particles. d. All of these statements are correct.

d The stomach secretes gastric juices containing hydrochloric acid (HCL) and the enzymes pepsin and gastric lipase, which chemically digest proteins and fats. In addition to the chemical breakdown of the nutrients, mechanical digestion mixes and churns the bolus until it becomes a liquid called chyme, at which point it is ready to enter the duodenum. The presence of chyme in the duodenum stimulates two important accessory organs, the gallbladder and the pancreas. These two organs assist in, but are not directly involved in, the digestion process. As fat enters the duodenum, the gallbladder contracts, secreting a greenish fluid called bile, which emulsifies the fat, breaking it into smaller particles.

Although the stomach contents are very acidic, the stomach usually does NOT cause damage to itself. Why? a. The stomach lining is quick to repair itself. b. The release of gastric juices is controlled to avoid too high a concentration. c. Mucus forms a thick protective coating for the stomach. d. Food and water dilute the gastric juices. e. All of the listed responses are correct.

e

When digested, fats are broken down into _____. a. glycerol only b. fatty acids only c. monosaccharides d. amino acids e. both glycerol and fatty acids

e

_____ is secreted by the _____ and acts to emulsify _____ in the _____. a. Lipase ... small intestine ... fats ... small intestine b. Trypsin ... pancreas ... fats ... small intestine c. Nucleases ... pancreas ... nucleic acids ... stomach d. Amylase ... salivary glands ... starch ... stomach e. Bile ... liver ... fats ... small intestine

e

Starch can be broken down into the disaccharide known as _____. a. lactose b. glucose c. sucrose d. fructose e. maltose

e Starch is composed of many maltose units.

A person with frequent heartburn is more likely than others to eventually develop this condition.

esophageal cancer

The gallbladder produces bile. false true

false liver produces bile

. When partly digested food enters the duodenum, this organ squirts bile into the small intestine.

gallbladder

Food is sent along the GI tract by means of a wavelike process called ________.

peristalsis

The region of the large intestine that when stretched stimulates the defecation reflex and allows for the passage of feces.

rectum

Three pairs of glands that secrete fluids, moisten and lubricate food, and contain digestive enzymes that hydrolyze starches.

salivary glands

The pancreatic duct and commom bile duct join and then empty into this organ.

small intestine

This organ in the digestive system functions to store food and break down proteins before transferring chyme to the duodenum.

stomach