2.4 - metabolism in conformers and regulators

Cards (27)

  • what is a conformer?
    an organism whose internal environment is dependent upon their external environment. they derive heat from surroundings
  • give 2 example of conformers?
    lizards and snakes
  • conformers have lower metabolic costs and occupy a narrower range of ecological niches
  • define a regulator?
    an organism that maintains their internal environment regardless of external environment. they derive heat from their metabolism
  • regulators have higher metabolic costs and occupy a wider range of ecological niches
  • advantages of conformers ?
    • lower metabolic costs
    • can tolerate variation in external environment due to behavioural responses
  • advantages of regulators?
    • occupy wider range of niches
    • adaptable to environmental change
  • define homeostasis ?
    the maintenance of the internal environment of an organism within tolerable limits despite changes in the external environment
  • Name species x and y
    A) Conformer
    B) Regulator
  • Homeostasis can also be called negative feedback
  • define thermoregulation?
    the ability of an organism to control its internal body temperature despite changes in external temperature
  • why is thermoregulation important for mammals?
    • their metabolism is dependent on enzymes, which are temperature dependent
    • they need to maintain high diffusion rates to maintain metabolism
  • what is the hypothalamus?
    temperature monitoring centre within the brain
  • how does the hypothalamus contribute to homeostasis?
    regulate temperature
  • Stages of homeostasis?
    Receptors -> control centre -> messenger -> effector -> corrective response -> system switched off
  • define receptor?
    detects changes in conditions outwith normal limits
  • define control centre?
    determines optimum level of internal environment and causes response when conditions are outwith this
  • define messenger?
    carries message from control centre to effector
  • Define effector?
    organ which responds
  • define corrective response?
    reverses original change and then switches off
  • Corrective responses for an increase in body temperature ?
    • sweating
    • vasodilation
    • hair erector muscles relax
    • decreased metabolic rate
  • corrective responses for a decrease in body temperature?
    • shivering
    • vasoconstriction
    • hair erector muscle contract
    • increased metabolic rate
    • decrease in sweat production
  • how does sweating cool down an organism?
    body heat is used to evaporate water in the sweat, cooling the skin
  • how does vasodilation cool down an organism?
    increased blood flow to the skin increases heat loss
  • how does shivering increase body temperature?
    skeletal muscle contraction generates heat
  • how does hair erector muscles contracting increase body temperature?
    raises hairs, trapping layer of insulating air
  • what is the importance of thermoregulation?
    optimal enzyme activity and high diffusion rates to maintain metabolism