Lecture 20

Question 1

Absorption of Nutrients by the Stomach:

Answer 1

Water (cold)
Electrolytes
Drugs
Fat content

Question 2

Gastric mucosal cells contain

Answer 2

alcohol dehydrogenase that converts some alcohol to acetaldehyde—–more of this enzyme found in males than females

Question 3

Females have less

Answer 3

total body fluid

Question 4

Release of chyme is regulated by

Answer 4

neural and hormonal reflexes

Question 5

Distention & stomach contents increase

Answer 5

secretion of gastrin hormone & vagal nerve impulses

Question 6

Enterogastric reflex regulates

Answer 6

amount released into intestines

Question 7

Vomiting (emesis):

Answer 7

Forceful expulsion of contents of stomach & duodenum through the mouth

Question 8

Cause of vomiting:

Answer 8

• irritation or distension of stomach

- unpleasant sights, general anesthesia, dizziness & certain drugs

Question 9

vomiting: Sensory input from medulla cause

Answer 9

stomach contraction & complete sphincter relaxation

Question 10

Vomiting: Contents of stomach squeeze

Answer 10

between abdominal muscles and diaphragm and forced through open mouth

Question 11

Vomiting: Serious because

Answer 11

loss of acidic gastric juice can lead to alkalosis

Question 12

Composition and Functions of Pancreatic Juice:

Answer 12

• pH of 7.1 to 8.2
• Contains water, enzymes & sodium bicarbonate
• Digestive enzymes

Question 13

Digestive enzymes of Pancreatic Juice:

Answer 13

• pancreatic amylase, pancreatic lipase, proteases
• ribonuclease—-to digest nucleic acids
• deoxyribonuclease

Question 14

Secretin

Answer 14

acidity in intestine causes increased sodium bicarbonate release

Question 15

GIP

Answer 15

fatty acids & sugar causes increased insulin release

Question 16

CCK

Answer 16

fats and proteins cause increased digestive enzyme release

Question 17

Histology of the Liver:

Answer 17

1. Hepatocytes arranged in lobules
2. Sinusoids in between hepatocytes are blood-filled spaces
3. Kupffer cells phagocytize microbes & foreign matter

Question 18

Blood Supply to the Liver:

Answer 18

1. Hepatic portal vein

2. Hepatic artery from branch off the aorta

Question 19

Hepatic portal vein:

Answer 19

nutrient rich blood from stomach, spleen & intestines

Question 20

Bile Production:

Answer 20

1. One quart of bile/day is secreted by the liver

- yellow-green in color & pH 7.6 to 8.6

Question 21

Components of bile:

Answer 21

• water & cholesterol
• bile salts = Na & K salts of bile acids
• bile pigments (bilirubin)

Question 22

Bilirubin:

Answer 22

globin

heme

Question 23

globin =

Answer 23

a reuseable protein

Question 24

heme =

Answer 24

broken down into iron and bilirubin

Question 25

Regulation of bile production:

Answer 25

1. parasympathetic impulses along vagus stimulates
2. Fatty acids and amino acids in chyme stimulate CCK
3. CCK causes contraction in gallbladder
4. Secretion enhances flow of bile

Question 26

Liver Functions–Carbohydrate Metabolism:

Answer 26

• Turn proteins into glucose
• Turn triglycerides into glucose
• Turn excess glucose into glycogen & store in the liver
• Turn glycogen back into glucose as needed

Question 27

Liver Functions –Lipid Metabolism:

Answer 27

• Synthesize cholesterol
• Synthesize lipoproteins
• Stores some fat
• Breaks down some fatty acids

Question 28

Liver Functions–Protein Metabolism:

Answer 28

• Deamination
• Converts NH3 into urea
• Synthesize plasma proteins
• Convert one amino acid into another

Question 29

Deamination =

Answer 29

removes NH2 from amino acids so can use what is left as energy source

Question 30

Other Liver Functions:

Answer 30

• detoxifies
• removes waste
• releases bile
• stores fat/ vitamins
• phagocytizes
• activates vit D