Ch. 25 The Digestive System McGraw-Hill

What are the four lobes of the liver?

Right, Left, Caudae, Quadrate

The substance that functions to moisten the mouth, clean the teeth, inhibit bacterial growth, and aid in swallowing by moistening food is

Saliva

What are functions of stomach acid

Activates pepsin and lingual lipase and destroys most ingested pathogens

What are stimuli for defacation?

Stretching of the descending colon, sigmoid colon, and rectum.

List the segments of the small intestine in order

Duodenum, Jejunum, Ileum

Within alveoli, collagen fibers called the _____________ ligament penetrate the bone on one side and the tooth on the other side.

periodontal

What are functions of the cheeks and lips?

Sucking

Pushing food between teeth for chewing

Speech articulation

Describe the role in eating of each of the following tooth types:

Premolars and Molars

Canines

Incisors

Premolars and Molars: Crush and Grind

Canines: Puncture and Shred

Incisors: Bite Off Pieces of Food

What are functions of the oral cavity?

Speech, Ingestion, and Respiration

The sac on the underside of the liver that serves to store and concentrate bile is the

Gallbladder

Describe segementation

Non-migrating constrictions and relaxations along the intestine

Describe each portion of the tooth:

Neck

Root

Crown

Neck: Where the crown, gum, and root meet

Root: The portion of the tooth below the gum

Crown: The portion of the tooth above the gum

What type of salivary glands are the parotid, submandibular, and sublingual glands?

Extrinsic

What is digestion?

The chemical and mechanical breakdown of food into a form usable by the body

When swallowing, a bolus of food moves from the mouth into the _________ before reaching the esophagus.

oropharynx

List the substrate for each of the following pancreatic enzymes:

Amylase

Ribonuclease

Lipase

Trypsin

Deoxyribonuclease

Amylase: Starch

Ribonuclease: RNA

Lipase: Fats

Trypsin: Proteins

Deoxyribonuclease: DNA

Longitudinal ridges within the mucosa of the anal canal are called the anal _________________.

Columns

Examples of mechanical digestion

Chewing

Churning of the stomach

Churning of the small intestine

The pancreatic islets are the _____________ portion of the pancreas, while the majority of the pancreas is an _____________ gland secreting enzymes and sodium bicarbonate

Endocrine, Exocrine

What is the outermost layer of the digestive tract wall?

Serosa

What is achieved with small intestinal muscle contractions?

Mixing chyme with intestinal juice, churning chyme and bringing it into contact with the mucosa for contact digestion and nutrient absorption, and moving residue toward the large intestine

The portion of the stomach between the fundus and the pyloric region is known as the ________________.

Body

List in order the passage of bile from its point of secretion in the liver to the duodenum.

Bile canaliculus - Bile ductule - Hepatic duct - Common hepatic duct - Bile duct

Which liver function contributes to the process of digestion?

Secretion of bile

What is the name of the narrowed distal region of the stomach?

Pyloric Region

The soupy mixture of semidigested food formed in the stomach is known as __.

Chyme

What is the function of pepsin?

To digest protein

What is found in saliva?

Lipase, Lysozyme, Water, Amylase, and Mucus

What are the three phases of gastric activity?

Cephalic, Gastric, and Intestinal

The depressions in the gastric mucosa are called gastric ____________.

Pits

The S shaped portion of the large intestine, located in the lower left quadrant, is the ______________ colon.

Sigmoid

How is water absorbed from the digestive tract?

Osmosis

What is the enzyme that digests dietary strach?

Pancreatic amylase

What is the action of pepsin?

Protein digestion

What is the action of carboxypeptidase?

Removes amino acids from the carboxyl group end of an amino acid chain

What is the action of dipeptidase?

Splits a molecule of two amino acids

What is the action of aminopeptidase?

Removes amino acids from the -NH2 end of an amino acid chain

What are the gastric rugae?

Longitudinal folds in the stomach lining

The primary function of the _________ intestine is to absorb water and electrolytes, but not other nutrients.

Large

What type of digestion occurs in the stomach?

Partial digestion of both protein and fat

What is deglutition?

swallowing

Describe dentin.

a yellowish tissue forming the bulk of the tooth

What two structures are essential for chewing, speech, sucking, and blowing?

Lips and Cheeks

What is ingestion?

The selective intake of food

What is the process of forcefully ejecting stomach or intestinal contents via the esophagus and mouth?

Vomiting

What is the straight muscular tube conveying food from he pharynx to the stomach called?

Esophagus

State another term for the process of chewing.

Mastication

What are the functions of saliva?

Aids in swallowing, cleanses mouth and teeth, and dissolves molecules so they can be tasted

Describe tooth enamel.

A cell free protective layer over the crown

Of the four tissue layer lining the lumen of the alimentary canal, the innermost tissue layer is called the _______________.

Mucosa

What is a goblet cell?

A mucus-secreting epithelial cell

What is the inactive precursor of pepsin?

Pepsinogen

Which portions of the large intestine are located in the pelvic cavity?

Rectum and anal canal

Enzymes that digest lipids are called

lipases

What is absorption?

The uptake of nutrient molecules from the digestive tract into the blood or lymph

What is the large intestine that excludes the cecum, recum, and anal canal called?

Colon

The large intestine begins with a pouch inferior to the ileocecal valve that is known as the

cecum

In order to improve fat digestion, large fat globules must first be dispersed into smaller droplets in a process called ___.

emulsification

What are the microscopic structural subunits of the liver?

Hepatic Lobules

The portion of the large intestine that passes horizontally across the abdominal cavity is the ______________ colon.

Transverse

Most taste buds are found associated with the _________ papillae of the tongue.

lingual

What is the function of chief cells?

Secrete pepsinogen

What is the function of mucus cells?

secrete mucus

What is the function of parietal cells?

Secrete hydrochloric acid

What is the function of enteroendocrine cells?

Secrete paracrine compounds

What is the hydrolysis of large dietary macromolecules into monomers known as?

Chemical digestion

True or False: The role of the liver in digestion is to produce digestive enzymes.

False, the pancreas produces digestive enzymes. The role of the liver is to produce bile for fat emulsion.

What are the functions of the large intestine?

Water and electrolye absorption

What are the final three centimeters of the large intestine called?

Anal canal

The digestion of starch by amylase results in the production of what?

Oligosaccharides and maltose

The portion of the large intestine found between the transverse and sigmoid colon on the left side of the abdominal cavity is the _________ colon.

Descending

Which blood vessels carry blood to the liver?

Hepatic portal vein and hepatic artery

Which phases of swallowing are involuntary?

Pharyngeal and Esophageal

The __________ is a spongy retroperitoneal gland posterior to the greature curvature of the stomach.

Pancreas

What is the substrate of:

Sucrase

Maltase

Lactase

Sucrase: Sucrose

Maltase: Maltose

Lactase: Lactose

What is found in bile?

Bile pigments

Minerals

Cholesterol

Phospholipids

Bile Acids

Micelles

Neutral fats

List pancreatic zymogens

Chymotrypsinogen

Trypsinogen

Procarboxypeptidase

Where is the cardiac region of the stomach located?

At the entry of the stomach

The segment of the digestive tract passing up the right side of the abdomen is the _______________ colon.

Ascending

What are the three layers of the muscularis externa of the stomach?

Longitudinal, Circular, and Oblique

What is a protease?

An enzyme that digests proteins

Which flexure is found between the ascending and transverse colon?

Right colic

What are the three components of gastric juice?

Pepsin, HCl, and water

What is found in intestinal juice?

Water and Mucus

The salivary glands located in the floor of the mouth just under the tongue are the _________ salivary glands.

Sublingual

Which salivary enzyme digests fats?

Lingual lipase

Retroperitoneal is best described as being located _____________the peritoeal cavity.

outside

Collectively, the teeth are known as the ______________.

Dentition

What protects the stomach lining from the acidic contents?

Mucous coat, Tight junctions, and Epithelial cell replacement

Where are bile canaliculi located?

between adjacent hepatocytes in the liver

Which components of bile are important in fat digestion and absorption?

Bile acids and lecithin

What is found in the pulp of the teeth?

Loose connective tissue, nerves, lymphatic vessels, and blood vessels

The mesentery that extends from the liver to the lesser curvature of the stomach is the __________ omentum.

Lesser

An enzyme called gastric ______________ digests dietary fats in the stomach.

lipase

What is the goal of the cephalic phase of gastric regulation?

To prepare the stomach for the arrival of food

Which tubular glands open into the gastric pits of the initial region of the stomach

cardial

The term ________ means pertaining to the mouth.

oral

Which are the functions of stomach acid?

Activates pepsin and lingual lipase, Denatures proteins, and Destroys pathogens

What is the uvula?

A projection of the posterior margin of the soft palate.

Which phase of gastric regulation occurs in response to food in the stomach?

Gastric phase