204 terms

Exam 3 (Digestive, Metabolism, Urinary)

Organs of alimentary canal
mouth, pharynx, esophagus, stomach, small intestine (duodenum, jejunum, ileum), large intestine (cecum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum), anus
Accessory digestive organs
teeth, tongue, gallbladder, salivary glands, liver, and pancreas
The major means of propelling food through the digestive tract is ___________.
Which digestive process normally occurs only in the mouth?
A) digestion
B) ingestion
C) propulsion
D) absorption
The _______ is the serous membrane that lines the body wall.
parietal peritoneum
The _______ circulation includes all of the arteries that serve the digestive organs.
The innermost tissue layer of the alimentary canal is the __________.
Saliva does not:
A) aid in the chemical digestion of proteins.
B) moisten food.
C) clean the mouth.
D) dissolve food chemicals so that they can be tasted.
A) aid in the chemical digestion of proteins
Which histological layer of the digestive tract is composed primarily of epithelial tissue?
The _______ guards the entry of food into the stomach.
cardiac sphincter
Which of the following is not a characteristic of the stomach?

A) The stomach mucosa is folded into rugae.
B) The stomach releases enzymes to digest carbohydrates.
C) The stomach has three layers of muscle in the muscularis tunic.
D) The stomach produces a double-layered coat of alkaline mucus.
B) The stomach releases enzymes to digest carbohydrates.
In the ________ of gastric secretion, chyme is moved into the duodenum.
intestinal phase
The _________ is the last segment of the small intestine.
Which of the following is not a structural modification of the small intestine to increase surface area?

A) Rugae
B) Villi
C) Microvilli
D) Circular folds
A) Rugae
What role of the stomach is essential to life?
production of intrinsic factor
Bile is produced by the:
The pancreas secretes:

A) bile.
B) secretin.
C) procarboxypeptidase.
D) cholecystokinin (CCK).
C) procarboxypeptidase
Most digestion and absorption of nutrients occurs in the:
small intestine
The major function of the large intestine is to:
absorb water
______ can result if food passes too slowly through the large intestine.
Proteins are digested into _______.
amino acids
Which is mismatched?

A) Protease: lipid digestion
B) Amylase: carbohydrate digestion
C) Lipase: fat digestion
D) Nuclease: DNA and RNA digestion
A) Protease: lipid digestion
Which organ of the digestive tract is the body's major digestive organ?
Small intestine
What is the major digestive function of the pancreas?
Production of digestive enzymes
Which part of the digestive system is the major location for absorption of the end products of digestion?
Small intestine
Which of the following is a water-soluble vitamin?

A) Vitamin A
B) Vitamin E
C) Vitamin C
D) Vitamin D
C) Vitamin C
Blood drained from the stomach is more alkaline (basic) than blood that serves the stomach. (True or False?)
Which enzymes are responsible for the final chemical breakdown of carbohydrates, amino acids, and nucleic acids?
Brush border enzyme
Which of the following is a water-soluble vitamin?

A) Vitamin B
B) Vitamin A
C) Vitamin D
D) Vitamin K
A) Vitamin B
Glycolysis occurs in the ______ of cells and is an _______ process.
cytosol; anaerobic
Which of the following is NOT a pathway in the oxidation of glucose?

A) glycolysis
B) Krebs cycle
C) gluconeogenesis
D) electron transport chain and oxidative phosphorylation
C) gluconeogenesis
Which hormone directs essentially all events of the absorptive state?
What is the most essential role of the liver?
protein metabolism
The body is able to form glucose from noncarbohydrate precursors. (True or False?)
Which hormone is called the "metabolic" hormone?
Which brain region is the main integrating center for thermoregulation?
Which of the following would only be found in the glomerular filtrate if the glomerular membrane were damaged?

A) protein
B) chloride
C) creatinine
D) glucose
A) protein
Where does most solute reabsorption occur in the nephron?
Proximal convoluted tubule
Approximately 80% of the energy used for active transport is devoted to the reabsorption of _______________.
What is the functional unit of the kidney?
What is the juxtaglomerular apparatus?
a system that regulates the rate of filtrate formation and systemic blood pressure
What type of capillaries make up the glomerulus?
In which part of the kidney is reabsorption (1) dependent upon the body's needs at the time, and (2) regulated by hormones?
Distal convoluted tubule
Chemicals that enhance urinary output are called _______________.
The _______ keeps the urethra closed when urine is not being passed from the bladder, and prevents leaking between voiding.
internal urethral sphincter
Digestion of which of the following would be affected the most if the liver were severely damaged?

A) proteins
B) carbohydrates
C) lipids
D) starches
C) lipids
Which of the following is not a characteristic of the stomach?

A) The stomach mucosa is folded into rugae.
B) The stomach releases enzymes to digest carbohydrates.
C) The stomach has three layers of muscle in the muscularis tunic.
D) The stomach produces a double-layered coat of alkaline mucus.
B) The stomach releases enzymes to digest carbohydrates.
The major means of propelling food through the digestive tract is ___________.
It is important to ensure that your diet is adequately rich in vitamins because ________.
most vitamins are coenzymes needed to help the body utilize essential nutrients
Which of the following enzymes is specific for proteins?

A) dextrinase
B) trypsin
C) amylase
D) lipase
B) trypsin
Glycolysis is best defined as a catabolic reaction based upon the ________.
conversion of glucose into two molecules of pyruvic acid
_________ is the key hormone regulator of the absorptive state.
Which part of the digestive system is the major location for absorption of the end products of digestion?
Small intestine
Pepsinogen, a digestive enzyme, is secreted by the ________.
chief cells of the stomach
Which nutrient molecule is the pivotal fuel molecule in the oxidative pathways?
Which of the following produce intrinsic factor?

A) enteroendocrine cells
B) zymogenic cells
C) mucous neck cells
D) parietal cells
D) parietal cells
The function of the hepatic portal circulation is to ________.
collect absorbed nutrients for metabolic processing or storage
Which hormone causes an increased output of enzyme-rich pancreatic juice and stimulates gallbladder contraction to release bile?
Gastrin, histamine, endorphins, serotonin, cholecystokinin, and somatostatin are hormones or paracrines that are released directly into the lamina propria. Which of the following cell types synthesize and secrete these products?

A) zymogenic cells
B) parietal cells
C) enteroendocrine cells
D) mucous neck cells
C) enteroendocrine cells
Which of the following nutrients yield the highest amount of energy per gram when metabolized?

A) proteins
B) vitamins and minerals
C) foods and beverages high in caffeine
D) fats
D) fats
True or False; The circular folds of the small intestine enhance absorption by causing the chyme to spiral, rather than to move in a straight line, as it passes through the small intestine.
Gluconeogenesis is the process in which ________.
glucose is formed from noncarbohydrate precursors
From the esophagus to the anal canal, the walls of every organ of the alimentary canal are made up of the same four basic layers. Arrange them in order from the lumen.
mucosa, submucosa, muscularis externa, and serosa
The primary function of cellular respiration is to ________.
break down food molecules and generate ATP
Define term: Peristalsis
Adjacent segments of alimentary tract organs alternately contract & relax, which moves food along the tract distally
Define term: Segmentation
Nonadjacent segments of alimentary tract organs alternately contract & relax, moving the food forward then backward.
When ______________ occurs, food mixing and food propulsion in small intestine slows.
What are the three mechanical digestion mechanisms?
chewing (mouth)
churning (stomach)
segmentation (small intestine)
Chewing occurs in the...
Churning occurs in the...
Segmentation occurs in the...
small intestine.
Ingestion occurs in the...
What are the main digestive system functions?
Digestion (mechanical & chemical)
What are the main mechanisms of propulsion?
swallowing (oropharynx) & peristalsis (esophagus, stomach, small intestine, & large intestine)
Where does swallowing occur?
Where does peristalsis occur?
Small intestine
Large intestine
Absorption occurs in the
small & large intestines (lymph & blood vessels)
Defecation occurs in the
Peristalsis is a mechanism of what digestive function?
Segmentation is a mechanism of what digestive function?
Mechanical digestion
Neural reflex pathways are initiated by what kinds of external stimuli?
Sight, smell, taste, & thought of food
What is the function of the visceral / parietal peritoneum?
to lubricate organs so that they glide as they move; greatly reduces friction
The blood supply through digestion:
1. Arterial
2. Celiac trunk (hepatic, splenic, left gastric)
3. Mesenteric (inferior, superior)
4. Venous
5. Drains (superior mesenteric, inferior mesenteric, splenic, cystic)
6. Hepatic portal system
7. Liver
8. (departs via...) Hepatic vein
In terms of the digestive system, the blood supply drains to the ______________ & empties into the _________, and finally departs via ___________.
hepatic portal system; liver; hepatic vein
What are the changes in the 4 layers from mouth to anus of alimentary canal? (innermost to outermost)
1. Mucosa (lines lumen)
2. Submucosa (glands & nerves/arteries/veins)
3. Muscularis externa (longitudinal muscle & circular muscle)
4. Serosa (attachment site & protection)
What layer of the alimentary canal lines the lumen?
What layer of the alimentary canal contains glands, nerves, arteries, and/or veins?
What layer of the alimentary canal is known as the attachment site and aids in protection?
The myenteric nerve plexus controls motility through __________ & ____________.
segmentation; peristalsis
True or false; The submucosal nerve plexus is linked to the autonomic nervous system.
False (the myenteric nerve plexus is linked to the ANS)
What are the two types of secretory cells found in the salivary glands?
serous cells (watery secretion of enzymes & ions)
mucous cells (stringy, viscous solution)
Describe serous cells of salivary glands
Watery secretion containing enzymes & ions
Describe mucous cells of salivary glands
Stringy, viscous solution
Saliva is largely ________
Is saliva hypertonic, isotonic, or hypotonic?
Is saliva acidic or basic?
slightly acidic
Saliva is slightly acidic due to its basic but varying components. What are these?
-Electrolytes (Na, Cl, HCO3, K, PO4)
-Salivary amylase
-Lingual lipase
What components of the saliva aid in protection?
-Lysozyme & IgA
-Defensins (local antibiotic) (specifically, cytokines)
-Metabolic wastes
What's the process of swallowing called?
5 phases/steps of deglutition (swallowing)
1. The upper esophageal sphincter is contracted. During the buccal phase, the tongue presses against the hard palate, forcing the food bolus into the oropharynx where the involuntary phase begins.
2. The uvula and larynx rise to prevent food from entering respiratory passageways. The tongue blocks off the mouth. The upper esophageal sphincter relaxes, allowing food to enter esophagus.
3. The constrictor muscles of the pharynx contract, forcing food into the esophagus inferiorly. The upper esophageal sphincter contracts (closes) after entry
4. Food is moved through the esophagus to the stomach by peristalsis.
5. The gastroesophageal sphincter opens, and food enters the stomach.
During the __________ phase, the tongue presses against the hard palate, forcing the food bolus into the oropharynx where the involuntary phase begins.
the buccal phase
Food is moved through the esophagus to the stomach by...
When the ____________ opens, food enters the stomach.
gastroesophageal sphincter
________ present in saliva helps dissolve food so it can be tasted & moistens it so tongue can compact it into a bolus.
Oral cavity and teeth are lubricated & cleansed by
Food is voluntarily placed into mouth through what major digestive function?
The voluntary buccal phase of deglutition (swallowing) is initiated by the tongue & propels food into the pharynx during what major digestive function?
Anatomical term meaning "chewing"
Mastication (chewing) by teeth & movements by tongue describes major digestive function?
Mechanical digestion
Peristaltic waves move food bolus to stomach, thus accomplishing involuntary (pharyngeal-esophagus) phase of deglutition during waht major digestive function?
Peristaltic waves mix food with gastric juice & propel it into the duodenum via what major digestive function?
Mechanical digestion
Digestion of proteins begun by pepsin is done via what major digestive function?
Chemical digestion
What are known as primarily food chutes?
Pharynx & esophagus
Mucus in stomach is produced to lubricate & protect stomach from _________.
________________ produced in stomach is required for the intestinal absorption of vitamin B12.
Intrinsic factor
The muscularis externa of the stomach is different from other areas/organs of the body. What's different?
It has a longitudinal layer, circular layer, AND *Oblique Layer
What are the three layers of the mucosa of the stomach?
Surface epithelium
Lamina propria
Muscularis mucosae
What cells of the mucosa produce intrinsic factor, which is needed for vitamin B12 absorption?
Parietal cells
Chief cells of mucosa produce...
___________ + ___________ = pepsin
pepsinogen + HCl = pepsin
_______________ is the protein digesting enzyme.
Histamine, serotonin, somatostatin, & gastrin are secreted into interstitial fluid by what cells?
Enteroendocrine cells (G)
Enteroendocrine cells (G) secrete its products into the....
interstitial fluid
____________ stimulates secretions / motility.
What are the vague possible causes of a stomach ulcer?
-Excess HCl production
-Spicy food
What are the two main causes of gastric ulcers?
NSAID & helicobacter pylori (H. pylori bacteria)
Chemicals released from NSAID & H. pylori bacteria do what?
-Reduce HCl
-Release ammonia
-Disrupt adhesion
-Release cytotoxin
-Promote inflammation
The holding area for digested food.
The stomach
True or False; The stomach degrades food both chemically & physically.
The stomach degrades food both chemically & physically into __________.
The stomach delivers chyme to the small intestine via ...
the duodenum.
T/F: In the stomach, alcohol & aspirin pass easily into mucosa.
What are the 3 peristaltic waves in the stomach?
1. Propulsion
2. Grinding
3. Retropulsion
During what peristaltic wave is the pyloric valve slightly opened?
True or false; Peristalsis is unidirectional.
False; it is bidirectional
T/F: Microvilli decrease surface area for digestion and absorption.
false; increase
In the small intestine, the mucosa changes. What are the changes?
-Circular folds (spiral through lumen)
-Brush border enzymes
-Peyer's patches
-Capillary bed
The circular folds of small intestine create a ________ flow.
A ____________ is a lymph capillary of the small intestine.
What enzymes digest proteins & carbohydrates?
Brush border enzymes
The pancreas empties into the ___________.
The _____________ of the pancreas produces insulin & glucagon.
Islets of Langerhans
Pancreatic juice is mostly...
Blood draining for pancreas is __________.
acidic (pH 8.0)
Pancreatic juice contains zymogen granules collectively called ___________.
protease (trypsin, carboxypeptidase, chymotrypsin, amylase, lipase, nuclease)
The large intestine empties through the...
The large intestine absorbs...
Na+ / K+
Vitamin K (synthesized)
B couples vitamins
Teniae coli
Haustra (puckers)
Epiploic appendages
Alimentary canal changes of the rectum
-Stratified squamous epithelium
-High abrasion
-Rectal valves
-Internal/External sphincters
What are the 6 major nutrient categories?
-Meat & beans
What food sources make steroids & bile salts?
Cholesterol & trans fatty acids
_________ - absorb fat-soluble vitamins; protection, cushion, insulating, source of energy; precursor; cell membranes
__________ - produce ATP
Fat soluble vitamins
Vitamin A
Vitamin D
Vitamin E
Vitamin K
Vitamins are needed in _________ amounts.
minute (small)
T/F: Vitamins are not used for energy.
Stages of metabolism of energy-containing nutrients.
1. Digestion in GI tract lumen to absorbable forms. Transport via blood to tissue cells.
2. Anabolism and catabolism of nutrients to form intermediates within tissue cells.
3. Oxidative breakdown of products of stage 2 in the mitochondria of tissue cells. CO2 is liberated, and H atoms removed are ultimately delivered to molecular oxygen, forming water. Some energy released is used to form ATP.
Metabolism of carbohydrates
-Glycolysis - Krebs cycle - Electron transport chain
-Glycogenesis - glycogenolysis - gluconeogenesis
Metabolism of lipids
-Oxidation of glycerol & fatty acids
-Lipogenesis and lipolysis
Metabolism of proteins
-Oxidation of amino acids
-Protein synthesis
4 basic organic molecules
1. Carbohydrates (sugar, starches)
2. Lipids (fats, triglycerides, cholesterol)
3. Proteins (structural elements, collagen, building blocks)
4. Nucleic Acids (genetic material/DNA)
What are the digestive enzymes?
Salivary amylase
Pancreatic amylase
Brush border enzymes (dextrinase, glucoamylase, lactase, maltase, and sucrase)
Major fuel used by body cells is...
Which metabolic oxidative phase does not require oxygen?
Structure that suspends the small intestine from the posterior body wall.
Fingerlike extensions of the intestinal mucosa that increase the surface area.
Folds of the small intestine wall.
Plicae circulares
Two anatomical regions involved in the physical breakdown of food.
Oral cavity & stomach
Organ that mixes food in the mouth.
Common passage for food and air.
Literally a food chute; has no digestive or absorptive role.
Folds of the stomach mucosa
Saclike outpocketings of the large intestine wall.
Projections of the plasma membrane of a cell that increase the cell's surface area.
Prevents food from moving back into the small intestine once it has entered the large intestine.
Ileocecal valve
Organ responsible for most food & water absorption.
Small intestine
Organ primarily involved in water absorption & feces formation.
Area between the teeth & lips/cheeks.
Blind sac hanging from the initial part of the colon.
Organ in which protein digestion begins.
Membrane attached to the lesser curvature of the stomach.
Lesser omentum
Organ into which the stomach empties.
Small intestine
Sphincter controlling the movement of food from the stomach into the duodenum.
Plyoric sphincter
Uvula hangs from its posterior edge.
Soft palate
Organ that receives pancreatic juice and bile.
Small intestine
Serosa of the abdominal cavity.
Parietal peritoneum
Region, containing two sphincters, through which feces are expelled from the body.
Anal canal
Anterosuperior boundary of the oral cavity; supported by bone.
Hard palate
Serous membrane forming part of the wall of the small intestine.
Visceral peritoneum
________ begins starch digestion in the mouth.
Glands that produce hydrochloric acid & pepsinogen.
Gastric glands
What hormone causes the liver to increase its output of bile?
What hormone causes the gallbladder to release stored bile?
What hormone stimulates increased production of gastric juice?
Two hormones that stimulate the pancreas to release its secretions.
Cholecystokinin & secretin
Three common simple sugars in our diet are
galactose, glucose, fructose
Disaccharides include
lactose, maltose, & sucrose
Fats are broken down to two types of building blocks, __________ & ________.
fatty acids & glycerol
Of the simple sugars, ___________ is most important; it is the sugar referred to as "blood sugar".
Gastrin represents a _________ stimulus.
Protein foods are largely acted on in the stomach by
The third layer of smooth muscle in the stomach wall allows mixing and mechanical breakdown by...
The important intestinal enzymes are
brush border enzymes
The small intestine is protected from the corrosive action of HCl in chyme by ___________, which is ducted by the pancreas.
bicarbonate-rich fluid
The pancreas produces protein-digesting enzymes, amylase, and nucleases. It is the only important source of...