Lecture 05

• What is the primary function of brown adipose tissue (BAT)?

  Heat generation (thermogenesis)
• How do mammals and birds generate heat?

  Through mechanisms of thermogenesis
• What is the relationship between thermogenesis and Basal Metabolic Rate (BMR)?

  Thermogenesis affects energy expenditure and BMR
• What are the consequences of adaptations in thermogenic systems?

  They affect human and animal populations
• What problems are associated with obesity and calorie intake?

  Health issues and metabolic disorders
• What factors influence heat production in complex organisms?

  Exercise, food intake, and environmental temperature
• What is the role of mitochondrial proton transport in thermogenesis?

  It enhances metabolic efficiency and heat production
• What do uncoupling proteins (UCPs) do in thermogenic reactions?

  They dissipate the proton gradient
• What is the physiological role of UCP1?

  It uncouples oxidative phosphorylation from ATP production
• What substrates do mitochondria use for energy production in BAT?

  Fatty acids and glucose
• How does mitochondrial density affect thermogenesis?

  Higher density enhances thermogenic capacity
• What is non-shivering thermogenesis?

  Heat generation without shivering
• Where is brown adipose tissue primarily located in newborns?

  Surrounding the kidneys and shoulder blades
• What causes the 'leaky' membrane in non-shivering thermogenesis?

  Thermogenin and differing genetic profiles
• What induces non-shivering thermogenesis?

  Thyroid hormones and adrenaline response
• What are the two types of adipose tissue mentioned?

  Brown Adipose Tissue (BAT) and White Adipose Tissue (WAT)
• From what type of stem cells does BAT develop?

  From the same stem cell type as muscle cells
• How does the Cafeteria Diet affect BAT mitochondria?

  It increases the activity of thermogenin
• What are the three types of uncoupling proteins (UCPs)?

  UCP1, UCP2, UCP3
• What is the role of UCPs in plants?

  They cause volatile amine release to attract insects
• What is the net result of one round of the hexokinase 'futile' cycle?

  Hydrolysis of one ATP molecule
• What is the energy equivalent for the hydrolysis of one ATP molecule?

  35 kJ of energy
• What is the effect of futile cycles within glycolysis/gluconeogenesis?

  They can be complex and involve different pathways
• What happens to pyruvate in anaerobic conditions?

  It is converted to lactate
• How does cytochrome oxidase differ in some human populations?

  It is more 'leaky' in certain populations
• What is the effect of cold environments on enzyme efficiency?

  It decreases enzyme efficiency
• What is the interaction between thyroxine and UCP proteins?

  Thyroxine stimulates UCP transcription
• How does dopamine (DA) affect oxygen consumption in BAT?

  DA stimulates oxygen consumption
• What happens to oxygen consumption in diabetic individuals?

  It is increased due to superoxide anion
• What is the effect of superoxide on unsaturated fatty acids?

  It generates precursors for lipid regulators
• How does diabetes affect mitochondrial functions?

  It leads to dysfunctional mitochondria
• What is the relationship between brown and white adipose tissue in cancer?

  WAT can convert to BAT under hormonal changes
• What inflammatory factor is mentioned in relation to cancer?

  Interleukin 6
• What happens to mitochondrial load in cancer?

  It increases along with thermogenesis
• What is the role of specific genes in obesity development?

  They influence fat storage and metabolism
• How does thermogenesis relate to exercise?

  Exercise increases thermogenic activity
• How does environmental temperature affect thermogenesis?

  Cold temperatures enhance thermogenic processes
• What are the physiological roles of proton transfer proteins?

  They facilitate heat production in thermogenesis
• How do mitochondrial types differ across tissues?

  Different tissues have specialised mitochondrial functions
• What changes occur in BAT as one ages?

  Some ATP synthase becomes present