PNP401 - Test 2 Questions and Correct
Answers
How does the GI system aid in attain nutrients? (3)
- digestion
- absorption
- metabolism
What are the components of the upper GI tract? (5)
1) mouth
2) pharynx
3) esophagus
4) stomach
5) duodenum
What are the components of the oral cavity? (3)
- cheeks
- hard and soft palates
- tongue
+ teeth
What occurs in the oral cavity?
1) initial phase of mechanism breakdown of food (mastication by teeth)
2) initial chemical digestion (Salivary amylase—starts chemical breakdown of carbohydrate)
What are the components of the pharynx? (3)
,1) Nasopharynx
2) Oropharynx
3) Laryngopharynx
What is the function of the pharynx?
Deglutition (swallowing)
Where is the esophagus in relation to the pharynx?
between the pharynx and stomach
What position is the esophagus normally in?
- closed except during swallowing
skeletal muscle at superior end—followed by smooth muscle
What does the esophagus do during swallowing?
- The soft palate is pulled upward.
- The vocal cords are approximated.
- The epiglottis covers the larynx.
- Respiration ceases.
- The bolus is seized by the constricted pharynx.
- Bolus of food moves into the esophagus.
Where is the swallowing center?
medulla oblongata
What does the swallowing center do?
coordinates the actions required to move food or fluid into the stomach without aspiration
,What cranial nerves are involved in swallowing? (4)
V (5)
IX (9)
X (10)
XII (12)
What happens after the bolus of food moves into the esophagus?
- distention of the wall, (peristalsis is initiated, pushing the food down the esophagus)
- The distal part of the esophagus passes through the hiatus (opening) in the diaphragm to join
the stomach
- The lower esophageal (gastroesophageal, or cardiac) sphincter relaxes in advance of the
bolus, allowing it to drop into the stomach.
What is the stomach?
muscular sac used to temporarily store food/fluid
How many layers of smooth muscle are in the stomach?
3
Aside from acting as a food/fluid reservoir what are other functions of the stomach?
- mix/churn food
- initial digestion of proteins (by pepsin)
- producing intrinsic factor
- form chyme
- absorb small lipid soluble molecules
, How is pepsin made?
pepsinogen + HCl
What are the primary tasks of the liver?
- Production of plasma proteins and clotting factors
- Breakdown of old and damaged erythrocytes
- Bile production
- Metabolism of carbs/proteins/fat
Where does the liver receive blood from?
hepatic portal vein
What does the hepatic portal vein transport to the liver in blood?
nutrients from intestine to liver
What ate hepatocytes?
the major parenchymal cells in the liver
What do hepatocytes do?
process nutrients and toxins
What is the pancreas?
a large gland behind the stomach that secretes digestive enzymes into the duodenum
What digestive enzymes are secreted by the pancreas?
- Trypsin
- Chymotrypsin
- Carboxypeptidase
Answers
How does the GI system aid in attain nutrients? (3)
- digestion
- absorption
- metabolism
What are the components of the upper GI tract? (5)
1) mouth
2) pharynx
3) esophagus
4) stomach
5) duodenum
What are the components of the oral cavity? (3)
- cheeks
- hard and soft palates
- tongue
+ teeth
What occurs in the oral cavity?
1) initial phase of mechanism breakdown of food (mastication by teeth)
2) initial chemical digestion (Salivary amylase—starts chemical breakdown of carbohydrate)
What are the components of the pharynx? (3)
,1) Nasopharynx
2) Oropharynx
3) Laryngopharynx
What is the function of the pharynx?
Deglutition (swallowing)
Where is the esophagus in relation to the pharynx?
between the pharynx and stomach
What position is the esophagus normally in?
- closed except during swallowing
skeletal muscle at superior end—followed by smooth muscle
What does the esophagus do during swallowing?
- The soft palate is pulled upward.
- The vocal cords are approximated.
- The epiglottis covers the larynx.
- Respiration ceases.
- The bolus is seized by the constricted pharynx.
- Bolus of food moves into the esophagus.
Where is the swallowing center?
medulla oblongata
What does the swallowing center do?
coordinates the actions required to move food or fluid into the stomach without aspiration
,What cranial nerves are involved in swallowing? (4)
V (5)
IX (9)
X (10)
XII (12)
What happens after the bolus of food moves into the esophagus?
- distention of the wall, (peristalsis is initiated, pushing the food down the esophagus)
- The distal part of the esophagus passes through the hiatus (opening) in the diaphragm to join
the stomach
- The lower esophageal (gastroesophageal, or cardiac) sphincter relaxes in advance of the
bolus, allowing it to drop into the stomach.
What is the stomach?
muscular sac used to temporarily store food/fluid
How many layers of smooth muscle are in the stomach?
3
Aside from acting as a food/fluid reservoir what are other functions of the stomach?
- mix/churn food
- initial digestion of proteins (by pepsin)
- producing intrinsic factor
- form chyme
- absorb small lipid soluble molecules
, How is pepsin made?
pepsinogen + HCl
What are the primary tasks of the liver?
- Production of plasma proteins and clotting factors
- Breakdown of old and damaged erythrocytes
- Bile production
- Metabolism of carbs/proteins/fat
Where does the liver receive blood from?
hepatic portal vein
What does the hepatic portal vein transport to the liver in blood?
nutrients from intestine to liver
What ate hepatocytes?
the major parenchymal cells in the liver
What do hepatocytes do?
process nutrients and toxins
What is the pancreas?
a large gland behind the stomach that secretes digestive enzymes into the duodenum
What digestive enzymes are secreted by the pancreas?
- Trypsin
- Chymotrypsin
- Carboxypeptidase
