The Liver

Question 1

Mechanism of Jaundice

Answer 1

• increased production of bilirubin
• decreased uptake of bilirubin by hepatocytes
• decreased ability of the liver to conjugate bilirubin

Question 2

Prehepatic Jaundice

Answer 2

• not related to the liver
• excessive breakdown of red blood cells
• increased unconjugated bilirubin in bloodstream
• dark faeces
• normal urine

Question 3

causes of prehepatic jaundice

Answer 3

• Gilberts syndrome - gene deficiency

neonatal - delays in clearance of bilirubin from red blood cell breakdown

Question 4

hepatic jaundice

Answer 4

• liver related
• liver loses ability to conjugate bilirubin
• mixture of both conjugated and unconjugated bilirubin

Question 5

causes of hepatic jaundice

Answer 5

• alcoholic liver disease

- viral hepatitis

Question 6

posthepatic jaundice

Answer 6

• obstruction of biliary drainage
• increased conjugated bilirubin
• pale faeces
• dark urine

Question 7

causes of posthepatic jaundice

Answer 7

obstruction of bile ducts caused by gall stones, disease of ducts (eg cancer) or compression of ducts

Question 8

where glucose goes when in absorptive state

Answer 8

liver –> glycogen
muscle –> glycogen
adipose tissue –> triglycerides
other tissues –> krebs

Question 9

where amino acids go in absorptive state

Answer 9

liver –> keto acids

muscle –> protein

Question 10

where triglycerides go in absorptive state

Answer 10

adipose tissue as fatty acids and glycerol –> triglycerides

Question 11

How to move from absorptive to post absorptive

Answer 11

• when you eat glucose increases
• glucose moves into beta cells in islets of Langerhans in pancreas by GLUT2
• triggers ATP generation from glucose metabolism and calcium influx
• calcium influx causes insulin exocytosis

Question 12

absorptive state to post-absorptive state

Answer 12

• blood glucose increases
• insulin secretion stimulated
• glucose uptake into cells (GLUT4)
• blood glucose concentration falls
• stimulus for insulin secretion removed
• blood insulin concentration falls - post absorptive state`

Question 13

what are the two types of reactions occurring in the post absorptive state

Answer 13

glucose supplying reactions - glycogenolysis, gluconeogenesis

glucose sparing reactions - beta oxidation of fats

Question 14

what are the hormones controlling the glucose supplying reactions

Answer 14

• fall in insulin

- increase in adrenaline, glucagon, cortisol and growth hormone