Chapter 24 - Digestive System

Question 1

Organs of the digestive system

Answer 1

esophagus, stomach, small intestine, large intestine, anal canal

Question 2

Accessory digestive organs

Answer 2

teeth, tongue, salivary glands, pharynx, liver, gallbladder, pancreas

Question 3

Ingestion

Answer 3

taking foods and liquids into the mouth

Question 4

Secretion

Answer 4

release water, acid, buffers, and enzymes into the lumen of the GI tract

Question 5

Motility

Answer 5

Alternating contractions and relaxations of smooth muscle in the walls of the digestive canal mix food and secretions and move them toward the anus

Question 6

Digestion

Answer 6

process of breaking down ingested food into small molecules that can be used by body cells

Question 7

Absorption

Answer 7

Movement of the products of digestion from the lumen of the digestive canal into blood plasma or lymph plasma

Question 8

Defecation

Answer 8

Removal of wastes, indigestible substances, bacteria and materials not absorbed

Question 9

Four basic tissue layers

Answer 9

Mucosa, submucosa, muscular layer

Question 10

3 layers of the mucosa

Answer 10

Epithelium, Lamina propria, muscularis mucosae

Question 11

Myenteric neural plexus

Answer 11

supplies the longitudinal and circular smooth muscle layers of the muscular layer, controls digestive canal motility

Question 12

Submucosal neural plexus

Answer 12

supply the secretory cells of the mucosal epithelium, controlling secretions of the organs of the digestive canal

Question 13

5 areas of the peritoneum

Answer 13

Greater omentum, falciform ligament, lesser omentum, mesentery, mesocolon

Question 14

Minor Salivary glands

Answer 14

glands that open directly, or indirectly via short ducts, to the oral cavity

Question 15

Three major salivary glands

Answer 15

Parotid glands, submandibular glands, sublingual glands

Question 16

Three major regions of a tooth

Question 17

Two enzymes that contribute to chemical digestion in the mouth

Answer 17

Salivary amylase, lingual lipase

Question 18

Function of salivary amylase

Answer 18

Begin starch digestion by breaking down starch into smaller molecules such as the disaccharide maltose, the trisaccharide maltotriose, and short-chain glucose polymers called a-dextrins

Question 19

Three parts of the pharynx

Answer 19

Nasopharynx, oropharynx, laryngopharynx

Question 20

Function of upper esophageal sphincter

Answer 20

regulates the movement of food from the pharynx into the esophagus

Question 21

Functions of the lower esophageal sphincter

Answer 21

regulates the movement of food from the esophagus into the stomach

Question 22

Three stages of swallowing

Answer 22

1) voluntary stage, 2) Pharyngeal stage, 3) Esophageal stage

Question 23

Functions of the stomach

Answer 23

1) Mixes saliva, food, and gastric juice to form chyme
2) Reservoir for food before release into the SI
3) Secretes gastric juice
4) Secretes gastrin into the blood

Question 24

Four regions of the stomach

Answer 24

Cardia, fundus, body, pyloric part

Question 25

Enzymes in the stomach

Answer 25

Pepsin, gastric lipase

Question 26

Function of pepsin

Answer 26

severs certain peptide bonds between amino acids, breaking down a protein chain of many amino acids into smaller peptide fragments

Question 27

Function of gastric lipase

Answer 27

Splits triglycerides in fat molecules into fatty acids and monoglycerides

Question 28

Components of the liver

Answer 28

Hepatocytes, Bile Canaliculi, Hepatic Sinusoids

Question 29

What are hepatocytes

Answer 29

Major functional cells of the liver and perform a wide array of metabolic, secretory, and endocrine functions

Question 30

What are bile canaliculi

Answer 30

Small ducts between hepatocytes that collect bile produced by the hepatocytes

Question 31

What are hepatic sinusoids

Answer 31

Highly permeable blood capillaries rows of hepatocytes that receive oxygenated blood from branches of the hepatic artery and nutrient-rich deoxygenated blood from branches of the hepatic portal vein

Question 32

What makes up the portal triad

Answer 32

Bile duct, branch of the hepatic artery, branch of the hepatic vein

Question 33

What makes up the hepatic acinus

Answer 33

Hepatocytes, bile duct system, hepatic sinusoids

Question 34

What supplies blood to the liver

Answer 34

Hepatic artery (oxygenated blood), hepatic portal vein (deoxyegenated blood)

Question 35

Role of bile

Answer 35

Excretory product and partially a digestive secretion, play a role in emulsification

Question 36

Functions of the liver (9)

Answer 36

Carbohydrate metabolism, lipid metabolism, protein metabolism, processing of drugs and hormones, excretion of bilirubin, synthesis of bile salts, storage, phagocytosis, activation of vitamin D

Question 37

3 regions of the SI

Answer 37

Duodenum, jejunum, ileum

Question 38

4 cell types in the epithelium of the SI

Answer 38

Absorptive cells (contain enzymes that digest food and absorb), Goblet cells (Secrete mucus), Paneth cells (secrete lysosome), Enteroendocrine cells

Question 39

Purpose of circular folds

Answer 39

Located in the mucosa and submucosa, enhance absorption by increasing surface area

Question 40

Two types of movement through the SI

Answer 40

Segmentations and a type of peristalsis called migrating motility complexes

Question 41

What does segmentation do

Answer 41

Mix chyme with the digestive juices and bring the particles of food into contact with the mucosa for absorption

Question 42

Functions of the LI

Answer 42

Completion of Absorption, production of certain vitamins, formation of feces, expulsion of feces from the body

Question 43

Movements through the SI

Answer 43

Haustral churning, peristalsis, mass peristalsis

Question 44

3 phases of digestion

Answer 44

Cephalic Phase, Gastric Phase, Intestinal Phase

Question 45

Cephalic phase

Answer 45

smell, sight, thought, or initial taste of food activates neural centers in the cerebral cortex, hypothalamus and brain stem, preparing the stomach for food that is about to be eaten