Chapter 24 - The Digestive System
The cecum directs waste into which structure of the large intestine?
ascending colon
Describe the roles of the liver and gallbladder in the digestion of fats.
bile salts emulsify large lipid globules into smaller droplets
Food that has been chewed and mixed with saliva that is soft and flexible is referred to as a
bolus
The head of the pancreas is located closest to the:
curve of the duodenum.
What is the function of pancreatic juice?
digesting starch
Bile secreted from the gallbladder and pancreatic juice secreted from the pancreas enter which portion of the GI tract?
duodenum
The smallest portion of the small intestine that is retroperitoneal is the
duodenum
In order for defecation to occur, the ___ must ___.
external anal sphincter; voluntarily relax
T/F: Enzymatic breakdown of food is a form of mechanical digestion.
false
T/F: The cells of the serous layer of the alimentary canal come in contact with food.
false
T/F: The esophagus lies anterior to the trachea.
false
T/F: The pancreas is the largest internal organ and heaviest gland of the body.
false
Which is NOT a function of the digestive system? ingestion filtration absorption defecation secretion
filtration
Which dome-shaped region of the stomach is located under the diaphragm?
fundus
The greater omentum attaches to which two organs in the abdominopelvic cavity?
greater curvature of the stomach and transverse colon
The peritoneal fold situated as a "fatty apron" anterior to the small intestine is the _____.
greater omentum
Hepatic sinusoids receives blood from
hepatic artery & hepatic portal vein
The teeth that are adapted to cut into food are
incisors
Where does the pharynx begin and end?
internal nares and larynx
The muscles that originate within the tongue and alter the shape of the tongue for speech and swallowing are
intrinsic muscles
Is control of the muscularis in the small intestine voluntary or involuntary?
involuntary
The ___ of the small intestine for the brush border that increases surface area for absorption and contain digestive enzymes.
microvilli
In what form are the products of lipid digestion absorbed?
monoglycerides and fatty acids
The cheeks, hard and soft palates, and the tongue form the
mouth
Cells in the stomach that produce factors needed for vitamin B12 absorption are
parietal cells
How does mechanical digestion occur in the stomach?
peristaltic waves in the stomach produce propulsion and retropropulsion of the food
The release of hydrochloric acid (HCl) into the lumen of the stomach is which basic process of digestion?
secretion
The type of movement in the small intestine that is a localized and mixing contraction of chyme is
segmentation
With aging, increased observations of duodenal ulcers, malabsorption, and maldigestion are associated with the
small intestine
Where along the GI tract is the muscularis composed of skeletal muscle?
superior part of esophagus
Which of the following is NOT a function of the gallbladder? concentrate bile store bile eject bile into the cystic duct synthesize bile
synthesize bile
Which organs of the digestive system come in contact with food and help to break it down?
teeth
How does the muscularis of the large intestine differ from that of the rest of the gastrointestinal tract?
the longitudinal muscles in the external layer condense and thicken to form teniae coli
What are the functions of gastric lipase and lingual lipase in the stomach?
to chemically breakdown triglycerides
A principal region of the large intestine is the
transverse colon, ascending colon, sigmoid colon
T/F: The gastrointestinal (GI) tract is found in the thoracic, abdominal and pelvic cavities.
true
T/F: The majority of nutrient digestion and absorption occurs in the small intestine.
true
The structure attached to the soft palate that helps close off the nasopharynx during swallowing is the _____.
uvula
The serous membrane on lining the surface of the stomach is the
visceral peritoneum
Which substances are absorbed in the large intestine?
water, vitamins, electrolytes
Which mechanical movement accurately describes the movement that occurs in the large intestine?
- strong peristaltic waves move mass colon contents from the transverse colon into rectum 3-4 times each day - when haustrum fills with contents, it contracts to move material into the next haustrum - peristalsis along the large intestine occurs at a slow rate (3-12 contractions per minute)