biochemistry

• What is the final end product of glycolysis which is later used to produce Acetyl CoA?

  Pyruvate
• Which enzyme catalyses the first step of glycolysis?

  Hexokinase and Glucokinase
• What is the fate of pyruvate in the muscle under anaerobic conditions?

  Converted to lactate
• What causes fructose intolerance?

  Decreased GLUT5 transporter activity
• What are the 2 major products of the pentose shunt?

  Ribose 5-phosphate and NADPH
• Pyruvate dehydrogenase complex converts...

  Pyruvate to Acetyl-CoA
• Pyruvate dehydrogenase complex is inactivated by...

  Phosphorylation and high energy charge (ATP, NADH, Acetyl-CoA)
• Pyruvate dehydrogenase complex is activated by...

  Dephosphorylation and low energy charge (ADP, pyruvate)
• What is the "first step" in the TCA cycle?

  Acetyl CoA combines with Oxaloacetate
• What drives ATP synthase rotation?

  H+ gradient across the mitochondrial inner membrane
• Which complexes can transport H+ ions OUT of the mitochondrial matrix?

  Complexes I, III and IV
• In which organ does gluconeogenesis mainly take place?

  Liver cells
• What promotes gluconeogenesis in the liver?

  High energy state, Acetyl CoA and Citrate
• Where does Glucose-6-phosphatase activity take place?

  Endoplasmic reticulum
• What reaction does Glucose-6-phosphatase catalyse?

  Glucose-6-phosphate → Glucose
• When does gluconeogenesis usually take place?

  In fasting state
• What causes alcoholic flush?

  Overactive ADH and underactive ALDH
• What reactions does ADH and then ALDH catalyse?

  Alcohol → Acetaldehyde → Acetate
• What is the activated form of glucose that serves as substrate for glycogen production?

  UDP-glucose
• Branching enzyme catalyses...

  Transfer glucose chain 1,4 linkage to 1,6 linkage
• Where is the majority of cholesterol produced?

  Liver
• What is the major starting material for cholesterol synthesis?

  Acetyl CoA
• What is the key regulatory enzyme for cholesterol synthesis?

  HMG-CoA reductase
• Which enzymes convert cholesterol to cholesterol esters?

  ACAT
• What is the function of lipoproteins?

  Transport of lipids around body
• How is cholesterol eliminated from body?

  Converted to bile salts
• Which type of enzymes break down dietary fat?

  Lipases
• What symptoms are displayed by patients with pancreatic lipase deficiency?

  Fatty stools and weight loss
• What is the main function of HDL?

  Transport of fat to the liver
• How do hormones mainly transmit their signal?

  Endocrine
• What is the target of corticotropin (ACTH)?

  Adrenal cortex
• Gonadotropin-releasing hormone (GnRH) is secreted from...

  Hypothalamus
• The first step in steroid hormone synthesis is the conversion of...

  Cholesterol into Pregnenolone
• Steroid hormone conversion is propagated mainly by which process?


  Hydroxylations
• In which glycerophospholipid do 2 phosphatidic acid groups share a single glycerol?

  Cardiolipin
• Which of the following is a sphingophospholipid?

  1. Lecithin
  2. Sphingomyelin
  3. Plasmalogen
  4. Cardiolipin


  Sphingomyelin
• Which are the most complex forms of sphingolipid?

  Gangleoside
• In which part of the cell are fatty acids for plasmalogens specially modified to fatty alcohols?

  Peroxisomes
• Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit which protein(s)?

  COX-1 and COX-2
• What is the precursor of eicosanoid hormones in humans?

  Arachidonate