Digestive System Flashcards Preview

Biology > Digestive System > Flashcards

Flashcards in Digestive System Deck (32):
1

Intracellular digestion

Occurs within the cell, often membrane bound vesicles

2

Extracellular digestion

Occurs outside of the cell, within lumen/tract

3

Outline the pathway of food starting from oral cavity.

Oral cavity --> Pharynx --> Esophagus --> Stomach --> Small intestine --> Large intestine -- Anus

4

What type of digestion occurs in the mouth?

-Mechanical (mastication) and chemical (salivary amylase)

5

Salivary amylase

-Breaks starch into maltose (disacc)

6

Peristalsis

-Rhythmic waves of involuntary muscular contractions
-Esophagus

7

What separate the stomach and esophagus?

-Lower esophageal (cardiac) sphincter

8

Compare the relative pressure of the thoracic and abdominal cavities

-Thoracic cavity (where body of esophagus is) negatively pressured relative to environment on inhalation
-Abdominal cavity (+) pressure

9

Gastroesphageal reflux disease (GERD)

-Results from pressure gradients
-Reflux of gastric material into esophagus

10

What are chief cells?

-In gastric glands
-Produce pepsinogen

11

What are parietal cells?

-In gastric glands
-Synthesize/release HCl and intrinsic factor (absorb vitamin B12)

12

What is the role of HCl?

-Converts pepsinogen to pepsin
-Kills bacteria

13

What kind of digestion is in stomach?

-Mechanical (churning) and Chemical

14

Where does chyme pass into?

-Duodenum through pyloric sphincter

15

What lines the stomach walls?

-Gastric mucosa secreted by mucous cells

16

Where does chemical digestion finish?

-Small intestine

17

What are the sections of the small intestine?

-Duodenum, Jejunum, Ileum

18

What do villi consist of?

-Capillaries and lacteals

19

Where do large fatty acids and glycerol go from the small intestine?

-Pass to lacteals then moved to liver where they're converted to tryglycerides

20

Which nutrients are actively absorbed?

-Amino acids and glucose

21

Where does most digestion in small intestines occur?

-Duodenum

22

What does intestinal mucosa secrete?

-Lipases
-Aminopeptidases
-Disaccharidases

23

Where and what is the function of gastrin?

-Produced by G cells in duodenum
-Stimulate histamine and pepsinogen secretion
-Stimulate parietal cells

24

Where and what is the function of intrinsic?

-Secreted by parietal cells
-Facilitate absorption of vitamin B12

25

Cholecystokinin (CCK)

-Produced by I cells of duodenal/jejunal mucosa
-Stimulate panreatic snzyme and somatostatin secretion
-Stimulate gallbladder contraction
-Hunger suppressant

26

Secretin

-Synthesized by S cells of upper intestine
-Stimulate secretion of bicarbonate-containing substances from pancreas
-Inhibit gastric emptying and gastric acid production

27

Bile

-Produced by liver and stored in gallbladder
-Release to small intestine to emulsify fats

28

What is the purpose of emulsifying fats?

-Increase surface area for lipases

29

What are functions of the liver?

-Store glycogen
-Convert ammonia to urea
-Protein synthesis
-Detoxification
-Cholesterol metabolism

30

What does the pancreas produce?

-Amylase, trypsin, lipase
-Secrete bicarbonate containing substances

31

Large intestine

-Absorb salt and any water not absorbed by small intestine

32

Rectum

-Transient storage of feces --> anus