Ch. 9: The Digestive System

Question 1

Intracellular digestion

Answer 1

Involves the oxidation of glucose and fatty acids to make energy

Question 2

Extracellular digestion

Answer 2

Occurs in the lumen of the alimentary canal

Question 3

Mechanical digestion

Answer 3

Physical breakdown of large food particles into smaller food particles

Question 4

Chemical digestion

Answer 4

Enzymatic cleavage of chemical bonds, such as peptide bonds of proteins or the glycosidic bonds of starches

Question 5

Pathway of the digestive tract

Answer 5

oral cavity, pharynx, esophagus, stomach, small intestine, large intestine, rectum

Question 6

Accessory Organs of Digestion

Answer 6

Salivary glands, pancreas, liver, and gallbladder

Question 7

Enteric Nervous System

Answer 7

Wall of the alimentary canal and controls peristalsis. Its activity is upregulated by the parasympathetic nervous sys and downregulated by the sympathetic nervous sys

Question 8

Hormones which regulate feeding behavior

Answer 8

Including antidiuretic hormone (ADH Or vasopressin) and aldosterone, which promote thirst; glucagon and ghrelin, which promote hunger; and leptin and cholecystokinin, which promote satiety

Question 9

Oral Cavity

Answer 9

Mastication (chewing) starts the mechanical digestion of food

Question 10

Salivary amylase and lipase

Answer 10

In the oral cavity, start the chemical digestion of food.

Question 11

Bolus

Answer 11

Food is formed into a bolus and swallowed

Question 12

Pharynx

Answer 12

Connects the mouth and posterior nasal cavity to the esophagus

Question 13

Esophagus

Answer 13

Propels food to the stomach using peristalsis.

Question 14

lower esophageal (cardiac) sphincter

Answer 14

Food enters stomach through the lower esophageal (cardiac) sphincter

Question 15

Parts of the stomach

Answer 15

Fundas, body, antrum, and pylorus

Question 16

Structure of the stomach

Answer 16

Lesser and greater curvature and is thrown into folds called rugae

Question 17

Mucous cells

Answer 17

Produce bicarbonate-rich mucus to protect the stomach

Question 18

Chief cells

Answer 18

Secrete pepsinogen, a protease activated by the acidic environment of the stomach

Question 19

Parietal cells

Answer 19

Secrete hydrochloric acid and intrinsic factor, which is needed for vitamin B12 absorption

Question 20

G-cells

Answer 20

Secrete gastrin

Question 21

Gastrin

Answer 21

A peptide hormone that increases HCl secretion and gastric motility

Question 22

Chyme

Answer 22

After mechanical and chemical digestion of food

Question 23

Pyloric sphincter

Answer 23

Food passes into the duodenum through this

Question 24

Duodenum:

Answer 24

First part of the small intestine and is primarily involved in chemical digestion

Question 25

Disaccharides

Answer 25

Brush-border enzymes that break down maltose, isomaltose, lactose, and sucrose into monosaccharides

Question 26

Brush-border peptidases

Answer 26

Include aminopeptidase and dipeptidase

Question 27

Enteropeptidase

Answer 27

Activates trypsinogen and procarboxypeptidase, initiating and activation cascade

Question 28

Secretin

Answer 28

Stimulates the release of pancreatic juices into the digestive tract and slows motility

Question 29

Cholecystokinin

Answer 29

Stimulates bile release from the gallbladder, release of pancreatic juices, and satiety

Question 30

Acinar cells

Answer 30

In the pancreas, produce pancreatic juices that contain bicarbonate, pancreatic amylase, pancreatic peptidases (trypsinogen, chymotrypsinogen, carboxypeptidases A and B) and pancreatic lipase

Question 31

Liver

Answer 31

Synthesizes bile, processes nutrients through glycogenesis and glycogenolysis, storage and mobilization of fats, and gluconeogenesis), produces urea, detoxifies chemicals, activates or inactivates medications, and synthesizes albumin and clotting factors.

Question 32

Bile

Answer 32

Can be stored in the gallbladder or secreted into the duodenum directly; emulsifies fats, making them soluble and increasing their surface area. Main components of bile are bile salts, pigments (especially bilirubin from the breakdown of hemoglobin) and cholesterol.

Question 33

Gallbladder

Answer 33

Stores and concentrates bile

Question 34

Jejunum and ileum

Answer 34

Of the small intestine, primarily involved in absorption

Question 35

Villi

Answer 35

The small intestine is lined w villi, which are covered with microvilli increasing the surface area available for absorption. They contain a capillary bed and lacteal

Question 36

Lacteal

Answer 36

A vessel of the lymphatic system; fat soluble compounds, such as fats, cholesterol, and fat-soluble vitamins, enter the lacteal

Question 37

Villi Capillary bed

Answer 37

Water soluble compounds such as monosaccharides, amino acids, water-soluble vitamins, small fatty acids, and water, enter the capillary bed

Question 38

Large intestine

Answer 38

Absorbs water and salts, forming semisolid feces

Question 39

Cecum

Answer 39

Outpocketing that accepts fluid from the small intestine through the ileocecal valve and is the site of attachment of the appendix

Question 40

Colon

Answer 40

Divided into ascending, transverse, descending and sigmoid portions

Question 41

Rectum

Answer 41

Stores feces, which are then excreted through the anus

Question 42

Gut bacteria

Answer 42

Produce vitamin K and biotin (vitamin B7)