A&P II CH. 22 Digestive System

Which of the following functions is not associated with the digestive system?

Filtration •Filtration is a function of the renal system, not the digestive system.

Which accessory organ stores bile?

Gallbladder

What cell produces bile?

Hepatocyte

What structure transports bile from the liver to the bile duct?

Common hepatic duct

Which digestive structure absorbs water and consolidates waste?

Large intestine

What component of a tooth is present in the crown, neck, and root?

Dentin

In what digestive organ is the acinar cell located?

Pancreas

What enzyme is responsible for digesting emulsified fats?

Pancreatic lipase -Pancreatic lipase breaks down emulsified triglycerides into free fatty acids and monoglycerides

Which of the following enzymes digests proteins?

Pepsin •Pepsin is secreted as pepsinogen by chief cells in the stomach and is activated by hydrochloric acid.

Which digestive structure is commonly called the "throat?"

Pharynx

In response to a steak dinner, certain secretions are needed to aid digestion. What cells in the pancreas would provide these secretions?

acing cells •Yes, in response to a high fat and protein meal, CCK would be stimulated and in turn would stimulate an enzyme-rich secretion from the pancreas.

Which is not an endocrine hormone secreted by the pancreas?

aldosterone •Aldosterone is a hormone secreted by the adrenal cortex, not the pancreas.

The secretion in the large intestine consists of which of the following?

bicarbonate- and potassium-rich mucus •Yes, an alkaline mucus secretion of bicarbonate and potassium protects the large intestinal wall from acids produced by resident bacteria.

Where are the enzymes for digestion of disaccharides and small polypeptides located?

brush border •Yes, the enzymes for digestion of disaccharides and small polypeptides are found in the brush border of most the absorptive cells of the small intestine.

Before carbohydrates are absorbed, __________ digest disaccharides into monosaccharides.

brush border enzymes

The breakdown products of which of the following are absorbed into lacteals?

fats *Yes, chylomicrons are absorbed into lacteals because they are too large to pass through the basement membrane of a capillary and into the blood.

Salivation is controlled almost entirely by the nervous system. Which of the following stimuli would inhibit salivation?

fear •Yes, fear, sleep, fatigue, and dehydration all inhibit salivation.

Which of the following tongue papillae do not contain taste buds?

filiform •Filiform papillae play no role in taste, and are instead covered with stratified squamous keratinized epithelium, which assists in mechanical digestion.

In the small intestine, which of the following enzymes breaks down maltose?

glucoamylase

Most digestive enzymes catalyze __________ reactions.

hydrolysis •Most digestive enzymes catalyze hydrolysis reactions—those that use a water molecule to break a bond between two molecules.

What is the final segment of the small intestine?

ileum

Villi in the small intestine ________________.

increase the surface area for absorption -Villi and other folds in the intestine increase the surface area available for absorption by a factor of 400 to 600.

During which phase in the control of the digestive system would bicarbonate and bile be stimulated?

intestinal phase *Yes, food in the intestines initiates a reflex that stimulates secretions of bicarbonate, digestive enzymes, and bile.

Which organ functions to absorb significant quantities of water, electrolytes, and vitamins?

large intestine

The most inferior division of the pharynx is the __________.

laryngopharynx •The laryngopharynx is part of the alimentary canal, as well as a passageway of the respiratory system.

The hepatic portal vein takes the breakdown products of nucleic acids to this organ for metabolism

liver

The gallbladder is located on the posterior side of the:

liver.

The pattern of slow, rhythmic contractions of the small intestine during fasting is called the __________.

migrating motor complex (MMC) •The MMC is responsible for moving undigested materials towards the colon. It is also what is responsible for the rumbling that occurs when a person is hungry.

The enzyme salivary amylase catalyzes the reactions that break polysaccharides into oligosaccharides in this organ

mouth

What do goblet cells secrete?

mucus •Goblet cells secrete mucus and are found in mucosae layers throughout the body.

Inactive precursors to enzymes are released by this organ to catalyze reactions that digest proteins in the small intestine

pancreas

Which of the following is not part of the gastrointestinal (GI) tract?

pancreas *The pancreas is an accessory organ of the digestive system, but is not part of the digestive tract.

Which of the following enzymes is important for the digestion of fat?

pancreatic lipase -Yes, pancreatic lipase is important for the digestion of fats. It is secreted by the pancreas and works in the small intestine.

The __________ cells of the stomach produce and secrete hydrochloric acid (HCl).

parietal -In addition to HCl, parietal cells also produce intrinsic factor, which is required for intestinal absorption of vitamin B12.

Which of the following enzymes is important for breaking down protein?

pepsin

Which of the following is paired incorrectly?

pepsin - oligopeptides *The stomach enzyme pepsin digests proteins into larger and smaller peptides.

The bolus is be able to move down the esophagus even if you are upside-down, because of __________.

peristalsis -During swallowing, the skeletal muscle and smooth muscle of the esophagus undergo peristalsis, which pushes the bolus inferiorly

Enzymatic breakdown of which of the following compounds doesn't begin until it reaches the stomach?

proteins

Which of the following does NOT increase surface area in the small intestine?

rugae

Which of the following GI hormones promotes a pancreatic juice rich in bicarbonate ions?

secretin -Yes, secretin (from S cells in the duodenum) causes both the liver and pancreas to secrete bicarbonate into the small intestine.

During the swallowing reflex __________.

the epiglottis closes off the glottis •During the swallowing reflex, the larynx elevates, and the epiglottis closes off the glottis to prevent entry of food or drinks into the larynx and trachea.

enteric nervous system

- supplies the alimentary canal from the esophagus to the anus (the terminal portion of the large intestine). -work with the sympathetic and parasympathetic nervous systems to control secretion from and motility of the alimentary canal.

The digestive system must perform the following six basic processes:

-INGESTION. -SECRETION. -PROPULSION. -DIGESTION. -ABSORPTION. -DEFECATION.

nerves of the sympathetic and parasympathetic divisions that serve the abdominal digestive organs are:

-celiac plexus, -superior mesenteric plexus, -inferior mesenteric plexus.

alimentary canal

-continuous passage through which food moves. -consists of the oral cavity (mouth), pharynx, esophagus, stomach, small intestine, and large intestine.

accessory organs

-not part of the alimentary canal but assist in digestion in some way. - include the teeth, tongue, salivary glands, liver, gallbladder, and pancreas.

Which of the following intestinal hormones stimulates the release of bile from the gall bladder?

CCK (cholecystokinin) •Yes, CCK causes the gall bladder to contract, releasing bile and an enzyme-rich pancreatic juice to be secreted from the pancreas.

Which tooth type is adapted for tearing and piercing?

Canine

Which layer of the alimentary canal is composed of simple squamous epithelium and areolar connective tissue?

Serosa

In what digestive organ is the parietal cell located?

Stomach

Which of the following functions is not associated with the liver?

Stores and concentrates bile •This is a function of the gallbladder, not the liver.

Which layer of the alimentary canal carries away absorbed nutrients?

Submucosa

Splanchnic circulation

The collection of blood vessels that supplies and drains the digestive organs in the abdominopelvic cavity.

Which accessory organ contains numerous filiform papillae?

Tongue

Which accessory organ contains cementum?

Tooth

Which structure is an extension of the soft palate?

Uvula

Enteric interneurons that are inhibitory to smooth muscle use which of the following neurotransmitters?

VIP (vasoactive intestinal peptide) -Yes, both VIP and NO (nitric oxide) are inhibitory to smooth muscle.

Which of the following vitamins is absorbed in the ileum after binding to intrinsic factor?

Vitamin B12 •Vitamin B12 is absorbed in the ileum after binding to intrinsic factor.

The esophagus empties into the __________ region of the stomach.

cardia -The cardia meets the esophagus at the cardiac orifice, which is a small opening that allows food to enter the stomach.

The first portion of the large intestine is the:

cecum.

Which of the following is a source of dietary fiber and promotes timely movement through the colon?

cellulose

HCl secretions convert pepsinogen to the active hormone pepsin. What cells in the gastric pits produce pepsinogen?

chief •Yes, chief cells produce pepsinogen, the inactive form of pepsin.

The largest folds in the small intestine are the __________.

circular folds (plicae circulares) •These folds not only increase surface area, but also slow down the transit of chyme through the small intestine, which gives the nutrients more time to be digested. These folds are about 1 cm high.

The gallbladder releases bile into the __________.

cystic duct •The gallbladder releases bile into the cystic duct upon stimulation with the hormone CCK.

An increase in HCl (hydrochloric acid) arriving in the duodenum would stimulate which hormone that would help to counteract the effects of HCl?

secretin •Yes, secretin stimulates the duct cells in the pancreas and liver to secrete a bicarbonate-rich solution that will bind hydrogen ions and increase the pH.

In what portion of the gastrointestinal tract does most salt and water absorption occur?

small intestine

Lipids are assembled into triglycerides and packaged into chylomicrons within enterocytes of this organ

small intestine

Most nutrient absorption in the GI tract occurs in the __________.

small intestine •About 90% of all nutrient absorption takes place in the small intestine.

The enzyme pepsin catalyzes reactions that digest proteins in this organ

stomach

Norepinephrine is the neurotransmitter released by which fibers?

sympathetic postganglionic fibers -Yes, norepinephrine is the neurotransmitter of the sympathetic postganglionic fibers. An increase in the sympathetic system would decrease digestion.