BIOL 2252 Digestive UPDATED ACTUAL Questions and
CORRECT Answers
Describe the functions of the digestive system and Functions of the digestive system:
differentiate between organs of the alimentary canal and Take in food
accessory digestive organs. Break down food into nutrient molecules
Absorb molecules into the bloodstream
Rid body of any indigestible remains
Alimentary canal (GI tract): Continuous muscular tube that runs from the mouth to
the anus.
Alimentary organs: mouth, pharynx, esophagus, stomach, small and large
intestine, anus.
Accessory digestive organs: salivary glands, liver, gallbladder, pancreas, teeth,
and tongue.
List and define the major processes occurring during Six essential activities:
digestive system activity Ingestion: eating
Propulsion: movement of food through the alimentary canal includes:
Swallowing
Peristalsis: major means of propulsion of food that involves alternating waves of
contraction and relaxation.
Mechanical breakdown: includes chewing, mixing food with salvia, churning food
and segmentation.
Segmentation: local constriction of intestine that mixes food with digestive juices.
Digestion: involves enzymes that break down complex food molecules into
chemical building blocks.
Absorption: passage of digested fragments from lumen of GI tract into blood or
lymph
Defecation: Elimination of indigestible substances via anus in from of feces.
Describe the location of the peritoneum Peritoneum: serous membrane of abdominal cavity that consist of
Visceral peritoneum: membrane on external surface of most digestive organs.
Parietal peritoneum: membrane that lines body wall.
Peritoneal cavity is the fluid filled space between two peritoneum's.
, What are mesenteries and what is they function? Mesentery is a double layer of peritoneum; layers are fused back-to-back.
Extends from body wall to digestive organs
Provides routes for blood vessels, lymphatics, and nerves
Holds organs in place and store fat.
Define retroperitoneal and name the retroperitoneal Retroperitoneal organs: located outside, or posterior to the peritoneum
organs of the digestive system. Includes most of pancreas, duodenum and parts of large intestine.
Describe the tissue composition and general function of Mucosa
each of the four layers of the alimentary canal. Functions:
Secretes mucus, digestive enzyme, and hormones
Absorbs end products of digestion
Protects against infectious disease
Has 3 sublayers:
Epithelium (simple columnar epithelium)
Lamina propria (loose areolar connective tissue)
Muscularis mucosae (smooth muscle)
Submucosa
Consist of areolar connective tissue
Contains blood and lymphatic vessels, lymphoid follicles, and submucosal nerve
plexus that supply surrounding GI tract tissue.
Has abundant amount of elastic fibers
Muscularis externa
Responsible for segmentation and peristalsis
Contains inner circular muscles layer and outer longitudinal layers
Serosa
Outermost layer that makes up visceral peritoneum
Made up areolar connective tissue covered with mesothelium
Serosa is absent in esophagus where it is replaced by adventitia (holds up
esophagus structure
Describe the 2 components (nerve plexuses) of the 1) Submucosal nerve plexus
enteric nervous system and their function - Regulates gland and smooth muscle in mucosa
2) Myenteric nerve plexus
- controls GI tract motility
What is the difference between short and long reflexes of Long reflexes: involve the CNS
the enteric nervous system? Short reflexes: occur entirely within the gastrointestinal wall.
Name examples of receptors and effectors involved in Respond to stretch , changes in osmolarity and pH
controlling GI tract activity When stimulated the receptors smooth muscle to mix and move lumen contents
reflexes can inhibit or activate digestive glands that secrete digestive juices or
hormones
Name the functions of the tongue -Gripping, repositioning, and mixing of food during chewing
-Formation of bolus, mixture of food and saliva
-Initiation of swallowing, speech, and taste
CORRECT Answers
Describe the functions of the digestive system and Functions of the digestive system:
differentiate between organs of the alimentary canal and Take in food
accessory digestive organs. Break down food into nutrient molecules
Absorb molecules into the bloodstream
Rid body of any indigestible remains
Alimentary canal (GI tract): Continuous muscular tube that runs from the mouth to
the anus.
Alimentary organs: mouth, pharynx, esophagus, stomach, small and large
intestine, anus.
Accessory digestive organs: salivary glands, liver, gallbladder, pancreas, teeth,
and tongue.
List and define the major processes occurring during Six essential activities:
digestive system activity Ingestion: eating
Propulsion: movement of food through the alimentary canal includes:
Swallowing
Peristalsis: major means of propulsion of food that involves alternating waves of
contraction and relaxation.
Mechanical breakdown: includes chewing, mixing food with salvia, churning food
and segmentation.
Segmentation: local constriction of intestine that mixes food with digestive juices.
Digestion: involves enzymes that break down complex food molecules into
chemical building blocks.
Absorption: passage of digested fragments from lumen of GI tract into blood or
lymph
Defecation: Elimination of indigestible substances via anus in from of feces.
Describe the location of the peritoneum Peritoneum: serous membrane of abdominal cavity that consist of
Visceral peritoneum: membrane on external surface of most digestive organs.
Parietal peritoneum: membrane that lines body wall.
Peritoneal cavity is the fluid filled space between two peritoneum's.
, What are mesenteries and what is they function? Mesentery is a double layer of peritoneum; layers are fused back-to-back.
Extends from body wall to digestive organs
Provides routes for blood vessels, lymphatics, and nerves
Holds organs in place and store fat.
Define retroperitoneal and name the retroperitoneal Retroperitoneal organs: located outside, or posterior to the peritoneum
organs of the digestive system. Includes most of pancreas, duodenum and parts of large intestine.
Describe the tissue composition and general function of Mucosa
each of the four layers of the alimentary canal. Functions:
Secretes mucus, digestive enzyme, and hormones
Absorbs end products of digestion
Protects against infectious disease
Has 3 sublayers:
Epithelium (simple columnar epithelium)
Lamina propria (loose areolar connective tissue)
Muscularis mucosae (smooth muscle)
Submucosa
Consist of areolar connective tissue
Contains blood and lymphatic vessels, lymphoid follicles, and submucosal nerve
plexus that supply surrounding GI tract tissue.
Has abundant amount of elastic fibers
Muscularis externa
Responsible for segmentation and peristalsis
Contains inner circular muscles layer and outer longitudinal layers
Serosa
Outermost layer that makes up visceral peritoneum
Made up areolar connective tissue covered with mesothelium
Serosa is absent in esophagus where it is replaced by adventitia (holds up
esophagus structure
Describe the 2 components (nerve plexuses) of the 1) Submucosal nerve plexus
enteric nervous system and their function - Regulates gland and smooth muscle in mucosa
2) Myenteric nerve plexus
- controls GI tract motility
What is the difference between short and long reflexes of Long reflexes: involve the CNS
the enteric nervous system? Short reflexes: occur entirely within the gastrointestinal wall.
Name examples of receptors and effectors involved in Respond to stretch , changes in osmolarity and pH
controlling GI tract activity When stimulated the receptors smooth muscle to mix and move lumen contents
reflexes can inhibit or activate digestive glands that secrete digestive juices or
hormones
Name the functions of the tongue -Gripping, repositioning, and mixing of food during chewing
-Formation of bolus, mixture of food and saliva
-Initiation of swallowing, speech, and taste
