Lecture 28 Unit 4

Question 1

what are the functions of the liver

Answer 1

• metabolism of carbohydrates, proteins, and lipids
• detoxifies the blood by removing drugs and hormones
• removes bilirubin
• releases bile salts to help digestion
• store fat soluble vitamins
• phagocytosis of worn out blood cells and bacteria
• vitamin D activation pathway

Question 2

what do kupffer cells do

Answer 2

phagocytize microbes and foreign matter

Question 3

what are hepatocytes

Answer 3

primary cells in the liver doing the most work

Question 4

how are hepatocytes arranged in lobules

Answer 4

in grids

Question 5

what are the spaces between the hepatocytes

Answer 5

blood-filled sinusoids or bile canaliculi

Question 6

what do bile canaliculi join to form

Answer 6

bile ducts which form hepatic ducts

Question 7

what do right and left hepatic ducts form

Answer 7

common hepatic duct

Question 8

what do cystic duct and common hepatic duct form

Answer 8

common bile duct

Question 9

what do common bile duct and main pancreatic duct empty into

Answer 9

duodenum

Question 10

what happens in carbohydrate metabolism in the liver

Answer 10

gluconeogenesis, glycogenesis, and glycogenolysis

Question 11

what happens in gluconeogenesis

Answer 11

• turns amino acids into glucose

- turns triglycerides into glucose

Question 12

what happens in glycogenesis

Answer 12

turn excess glucose into glycogen and store in the liver

Question 13

what happens in glycogenolysis

Answer 13

turns glycogen back into glucose

Question 14

what happens in lipid metabolism in the liver

Answer 14

• synthesize cholesterol
• synthesize lipoproteins
• stores some fat
• breaks down some fatty acids

Question 15

what lipoproteins are synthesized in the liver and what do they do?

Answer 15

HDL and LDL which are used to transport fatty acids and cholesterol in the bloodstream

Question 16

what happens in protein metabolism in the liver

Answer 16

deamination, transamination, converts toxic ammonia into urea, synthesizes plasma proteins

Question 17

how is urea excreted

Answer 17

by the kidney

Question 18

what are plasma proteins used for

Answer 18

in the clotting mechanism and immune system

Question 19

what are the functions of the large intestine

Answer 19

• smooth muscle mechanical digestion
• peristaltic waves
• haustral churning
• bacteria ferment undigested carbohydrates
• gastroilial reflex
• gastrocolic reflex
• defecation reflex

Question 20

what happens in haustral churning

Answer 20

relaxed pouches are filled from below by muscular contractions and when full they contract and ove content to next pouch

Question 21

what do bacteria in the large intestine ferment

Answer 21

undigested carbohydrates into carbon dioxide and methane gas and undigested proteins into simpler substances

Question 22

what happens in the gastroilial reflex

Answer 22

when stomach is full gastrin hormone relaxes ileocecal sphincter msg small intestine will empty into large intestine

Question 23

what happens in the gastrocolic reflex

Answer 23

when stomach fills a strong peristaltic wave moves contest of transverse colon into rectum

Question 24

what happens in defecation reflex

Answer 24

when rectum fills, input to sacral spinal cord return commands to expel feces

Question 25

what are the steps in the defecation reflex?

Answer 25

1. gastrocolic reflex moves feces into rectum
2. stretch receptos signal sacral spinal cord
3. parasympathetic nerves contract muscles of rectum and relax internal anal sphincter
4. external anal sphincter is voluntarily controlled