Intro to metabolism

• What is metabolism?

  A set of chemical reactions essential for life
• What are the two main types of metabolic reactions?

  Catabolic and anabolic reactions
• What do catabolic reactions involve?

  Breakdown of organic matter to produce energy
• What do anabolic reactions involve?

  Synthesis of complex molecules, consuming energy
• What are examples of fuel stores in metabolism?

  Glycogen and fat
• What are the steps in anabolism?

  1. Form precursors
  2. Form complex molecules from simple precursors
  3. Link these complex molecules together
• What is an example of catabolism?

  Carbohydrate (starch) to glucose
• What is an example of an anabolic process?

  Glucose used to make glycogen
• What is ATP?

  A high energy phosphate group
• What is NADH?

  High energy electrons, reducing power
• What is the role of ATP in the cell?

  Energy carrier for cellular processes
• What happens during ATP hydrolysis?

  ATP is converted to ADP and releases energy
• What is the ΔG in metabolic reactions?

  Energy available to do work
• What does a positive ΔG indicate?

  An unfavourable reaction requiring energy
• What does a negative ΔG indicate?

  A favourable reaction releasing energy
• What is the goal of food metabolism?

  Generate energy in the form of ATP
• What is the first step in glucose metabolism?

  Conversion of glucose to glucose-6-phosphate
• What is the role of glucokinase/hexokinase?

  Enzyme that catalyzes glucose phosphorylation
• What is the ΔG for the conversion of glucose to glucose-6-phosphate?

  ΔG = +3.3 kcal/mole
• How does ATP hydrolysis affect unfavourable reactions?

  It drives energetically unfavourable reactions
• What happens to NAD+ during redox reactions?

  NAD+ is reduced to NADH
• What is the function of mitochondria?

  Production of ATP through cellular respiration
• What is the final acceptor of electrons in the electron transport chain?

  Oxygen
• What are the main metabolic pathways involved in energy production?

  1. Glycolysis
  2. TCA cycle
  3. Electron transport chain
• What is the maximum ATP yield from one glucose molecule?

  36 or 38 ATP
• What is oxidative phosphorylation?

  Process of ATP generation in the electron transport chain
• What do reduced coenzymes donate in the electron transport chain?

  A pair of electrons to electron carriers
• What happens to energy as electrons pass down the electron transport chain?

  Energy is lost and used to generate ATP
• What is the principal storage form of energy in adipose tissue?

  Triglycerides
• Where is the electron transport chain located?

  Inner mitochondrial membrane
• What is produced during aerobic ATP production?

  ATP
• What is the maximum ATP yield from one glucose molecule?

  38 ATP
• How many ATP are produced from glycolysis?

  2 ATP
• What is the role of NADH in ATP production?

  It donates electrons to the electron transport chain
• What happens to pyruvate under anaerobic conditions?

  Converted to lactate
• What is the TCA cycle's role in metabolism?

  Provides intermediates for anabolic reactions
• What is the significance of oxaloacetate in gluconeogenesis?

  It is used to synthesize glucose
• What is feedback inhibition in metabolic pathways?

  NADH inhibits its own production enzymes
• How does hormonal regulation affect metabolism?

  Insulin and glucagon regulate metabolic pathways
• What occurs during hypoxia/anoxia?

  Oxidative phosphorylation fails