Chapter 24 Reading Assignment
the muscularis of the stomach consists of ______ layers.
3
the esophagus is in the
mediastinum
starch digestion occurs in the
mouth, small intestine
T/F: food regardless of type moves out of the stomach within 1.5 hours
False
T/F: the majority of the muscularis consists of two layers of skeletal muscle
False. It's smooth muscle
T/F: most of the nervous control of the digestive system is through the parasympathetic nervous system
False. It's through the Enteric Nervous System
match the layer of the digestive tract with the correct description
Mucosa --> Consists of an epithelial lining, a layer of connective tissue referred to as lamina propria and a thin layer of muscle Muscularis --> Throughout most of the digestive tract, this tunic consists of two layers of smooth muscle: an inner circular layer, and an outer longitudinal layer Serosa --> Consists of a thin layer of connective tissue and simple squamous epithelium Submucosa --> Consists of a thick layer of connective tissue containing nerves, blood vessels, lymphatics and glands
what is a mesentery?
a connective tissue sheet composed of two layers of serous membranes
describe a hepatic lobule
a hexagon-shaped tissue with a portal triad at each corner
which are functions of the digestive tract?
absorb water, digest food, absorb electrolytes
name the outermost or most superficial layer of the digestive tract
adventitia/serosa
the ____________ part of the tongue is freely moveable
anterior
select the mechanisms that regulate the digestive system
chemical signals, nervous mechanisms
identify the hormones that decrease gastric secretions and gastric motility
cholecystokinin, secretin
stomach contents are called
chyme
what is the function of HCO3- when it is secreted by the large intestine
in increases the pH of the feces, which are acidic because of bacterial secretions
identify the functions of HCl is the stomach
inactivates salivary amylase, destroys ingested bacteria, activates pepsin
structures that secrete lipase include:
lingual glands, pancreas
identify the functions of saliva
moistens food in the oral cavity, neutralizes bacterial acids, digests starch
identify the primary products of the chemical digestion of lipids
monoglycerides, fatty acids
identify the substances within saliva
mucin, bicarbonate ion, lysozyme, amylase, water
identify the part of the pharynx that does not typically function in digestion
nasopharynx
the serous membrane that covers the interior surface of the abdominal cavity is the _______________.
parietal peritoneum
intrinsic factor is secreted by the ______________ cells of the _____________
parietal, stomach
the inflammation of the peritoneal membranes is called
peritonitis connective
the abdominal cavity is lined by ____________ membranes which produce a thin, lubricating film
serous
describe the membranes that line the abdominal cavity
serous membranes that secrete a serous lubricating fluid
segmental contractions are mixing contractions that occur predominantly in the ________________.
small intestine
the chemical digestion of disaccharides occurs in the
small intestine
what type of muscle makes up most of the muscularis of the GI tract?
smooth
cholecystokinin, secretin, and the vagus nerve all _____________ the release of pancreatic juice
stimulate
T/F: the masseter and temporals are muscles that move the mandible during mastication
true
T/F: villi an microvilli of the small intestine serve to increase surface area to allow for greater digestion and absorption
true
identify what activates chymotrypsinogen and procarboxypeptidase
trypsin
identify what activates trypsinogen
trypsin, enterokinase
identify the small blind-ended tube attached to the cecum
vermiform appendix
match the oral cavity region to its description
vestibule --> space between the lips and teeth oral cavity --> space medial to the teeth
identify the MACROscopic fingerlike projections of the small intestine that increase surface area for increased absorption
villi
identify the features of the small intestine that function to increase surface area and thus enhance digestion and absorption
villi microvilli circular fold
the serous membrane that covers the organs of the abdominal cavity is the ________________ peritoneum
visceral
Explain the process of bicarbonate ion production in the pancreas.
CO2 and H2O combine under the influence of carbonic anhydrase to for H2CO3 Carbonic acid dissociates into H+ and HCO3- H+ exchanged for Na+ in the blood HCO3- is exchanged for Cl- in the intercalated ducts. Na+ and H20 follow the HCO3- HCO3-, Na+, and H2O move into the interlobular ducts
Identify the steps in the production of hydrochloric acid by the stomach from beginning to secretion into the stomach.
CO2 diffuses into parietal cell CO2 combines with H2O to form H2CO3 H2CO3 dissociates HCO3- is exchanged for Cl- with the bloodstream H+ pumped into the duct of the gastric gland Diffusion of Cl- into duct of gastric gland
place the events of the cephalic phase of gastric regulation in order beginning from initiation of the cephalic phase
Taste, smell, or thought of food Stimulation of medulla oblongata Parasympathetic impulses carried by vagus nerve Postganglionic neurons stimulate the secretion of gastin and histamine Gastric secretions are released
T/F: throughout the digestive tract, the muscularis consists of 2 layer, except the stomach, which has 3 layers
True
match the digestive enzyme with the structure that secretes it
Trypsin --> pancreas Disaccharides --> small intestine Bile salts --> liver Amylase --> salivary glands Peptidase --> small intestine Pepsin --> stomach
correctly pair each basic function of the digestive system with the correct description
absorption --> movement of molecules from digestive tract into the circulation or lymphatic system digestion --> breakdown of large organic molecules into their component parts mastication --> process by which teeth break down food into smaller particles to increase SA ingestion --> the intake of solid or liquid food into the stomach propulsion --> movement of food from one end of the digestive tract to the other
which of the following is an example of nutrient conversion?
amino acids are converted to glycogen
the hepatic portal triad consists of 3 vessels. The hepatic portal vein, the hepatic _____________, and the hepatic ____________.
artery, duct
the four parts of the colon from proximal to distal end are the
ascending transverse descending sigmoid colon
match the components of pancreatic juice with the correct function
bicarbonate ion --> raise pH of small intestine proteolytic enzymes --> chemical digestion of proteins amylase --> chemical digestion of polysaccharides lipase --> chemical digestion of fats nuclease --> chemical digestion of DNA and RNA
identify the components of pancreatic juice
bicarbonate ions enzymes to digest lipids enzymes to digest carbs enzymes to digest proteins
the emulsification of lipids occurs primarily though the action of ________________.
bile salts
identify the components of bile
bile salts, bilirubin, mucus, cholesterol, lecithin
all of the microvilli on the epithelial surface of the small intestine are collectively called the
brush border
the muscle in the cheeks is called the _____________.
buccinator
identify the mismatch pair of enzyme and substrate below
carboxypeptidase - lipids
match the parts of the stomach with the correct description
cardiac sphincter - constrictor between the esophagus and stomach pyloric sphincter - constrictor between the stomach and small intestine body - largest part of the stomach fundus - rounded superior portion of the stomach pyloric part - funnel shaped part of the stomach
the ____________ sphincter is between the esophagus and the stomach, and the ______________ sphincter is between the stomach and the small intestine
cardiac, pyloric
the proximal end of the large intestine is characterized by a pouch-like structure called the
cecum
the vermiform appendix is attached to the
cecum
the large intestine consists of the __________, _____________, _____________, and anal canal
cecum colon rectum
the taste, smell, or thought of food stimulates gastric secretions by activating the ____________ phase of gastric regulation
cephalic
a type of lipoprotein consisting of mostly triglycerides along with phospholipids, cholesterol, and protein is a(n)
chylomicron
mass movements occur in the
colon
teniae coli are bands of longitudinal muscle of the _________ that from haustra upon contraction
colon
identify the functions of the gallbladder
concentration of bile storage of bile
the submucosa consists of ______________ tissue
connective
identify the duct leading from the gallbladder
cystic duct
select the effects of aging on the digestive system
decreases the amount of mucus secretion decline in the liver's ability to detoxify chemicals reduction of motility thinning of tooth enamel
feces are eliminated form the body by process of
defecation
the elimination of semi-solid waste products from the body is called
defecation
the process that moves a bolus from the oral cavity into the esophagus is called swallowing or ______________.
deglutition
describe the functions of hepatocytes
detoxification, bile production, synthesis of blood components, phagocytosis
the system specialized to ingest/digest food and absorb water/electrolytes is the
digestive system
The three sections of the small intestine, listed in order as food passes through
duodenum --> jejunum --> ileum
place the segments of the small intestine in the order of which food travels
duodenum --> jejunun --> ileum
the process by which bile salts transform large lipid droplets into much smaller lipid droplets is called
emulsification
food is ingested, digested, and finally eliminated from the body as ______________.
feces
the organ that stores and concentrates bile is the ____________________
gallbladder
identify the secretions of the stomach
gastin, pepsinogen, mucus, Hal, intrinsic factor
Mass movements in the colon are initiated by the ______ reflex when there is food in the stomach and by the ______ reflex when there is food in the small intestine.
gastrocolic, duodenocolic
identify the pouches of the large intestine that result from contraction of the teniae coli
haustra
identify the vessels that empty into the hepatic sinusoids
hepatic artery hepatic portal vein
the blood-filled channels found between the hepatic cords are called
hepatic sinusoids
bile helps in ________ the pH of the small intestine to allow for normal function of pancreatic enzymes
increasing
identify the structures of the digestive tract that are lined with simple columnar epithelium
large intestine, stomach, small intestine
a micelles is a ________ droplet surrounded by _________.
lipid, bile salts
a chylomicron is a ___________ droplet surrounded by __________
lipid, proteins
fatty acids and glycerol are products of the chemical digestion of
lipids
describe how lipids are transported through the blood
lipids are combined with protein to form lipoproteins
the ________ are formed mostly by the orbiculares iris and connective tissue covered by skin
lips
identify the largest internal organ of the body
liver
identify the organs of the digestive system that are considered accessory organs
liver, pancreas, salivary glands, gallbladder
the stongs and infrequent peristaltic contractions that move contents of the large intestine longer distances are called
mass movements
which movements of the digestive tract will help to propel food form one end of the digestive tract to the other?
mass movements, deglutition, peristalsis
what are the basic functions of the digestive system?
mastication, defecation, absorption, ingestion, digestion
mastication is the
mechanical breakdown of food (chewing)
acetylcholine, norepinephrine, and serotonin are _____________ that affect digestive tract ______________.
neurotransmitters, motility
correctly pair the digestive secretion with the correct function
ntrinsic factor --> B12 absorption Trypsin --> digests proteins Amylase --> digests starch Hydrochloric acid --> activates pepsin Enterokinase --> activates trypsin Bile salts --> emulsifies lipids Pepsinogen --> active form aids in breaking proteins Gastrin --> stimulated gastric secretions
identify the muscle that forms most of the lips
orbicularis oris
Identify the structures of the digestive tract that are lined with stratified squamous epithelium
oropharynx, esophagus, mouth, anal canal
identify the sturctures that are involved in deglutition
oropharynx, esophagus, tongue
the _______________ is an organ that consists of a head located within the curvature of the duodenum and a tail that extends to the spleen
pancreas
the three large paired salivary glands are the _____________, _____________, and _____________.
parotid, sublingual, submandibular
match the digestive secretion with the correct function
pepsin --> digests proteins into smaller peptide chains lipase --> digests lipids bicarbonate ions --> provides appropriate pH pancreatic enzymes mucus --> protects the lining of the esophagus peptidases --> splits amino acids from polypeptides bile salts --> emulsifies lipids
identify the substances that aid in the chemical digestion of proteins
peptidases carboxypeptidase trypsin pepsin
identify the secretions of the small intestine
peptidases, mucus, disaccharidases, cholecystokinin, secretin
teeth found in an adult mouth are called ___________, which teeth found in a chlid's mouth are called _______________.
permanent, deciduous
identify the functions of the liver
production of bile, synthesis of new molecules, interconversion of nutrients, phagocytosis, storage of glycogen/lipids/vitamins/minerals, production of blood proteins, conversion of amino acids into carbs, nutrient storage
identify the functions of mucus secretion in the large intestine
protects intestinal lining, helps fecal matter stick together, lubricates colon wall
trypsin, chymotrypsin, and pepsin all aid in the chemical digestion of _____________
protein
peristaltic contractions that move chyme through the partially closed pyloric opening are called the ________________
pyloric pump
identify the functions of bile
raises pH of small intestine emulsification of lipids
what process mixes food with digestive secretions?
segmental contractions
identify the types of movements that occur within the small intestine
segmental contractions peristaltic contractions
the adventitia or _____________ is the outermost layer of structures in the digestive system
serosa
identify the organ of the digestive system that primarily functions as a storage and mixing chamber
stomach
pepsinogen and pepsin are both secretions of the ____________
stomach
lipid digestion occurs in the
stomach, small intestine
the layer of the digestive tract that is a thick layer of connective tissue containing nerves, blood vessels, lymphatics, and glands is the
submucosa
identify the four muscles of mastication
temporalis, medial pterygoid, masseter, lateral pterygoid
the low pH of the stomach is due to
the action of the proton pump
what is the brush border
the microvilli of the epithelium in the small intestine
describe the effects of food intake on the stomach
the rugae flatten and the stomach volume increases
name factors that influence stomach emptying
the type of food the volume of food