B4- Metabolism in Conformers and Regulators

• The ability of an organism to maintain its metabolic rate is affected by external abiotic factors
• Abiotic factors are found in the environment:

  • Temperature,
  • Humidity,
  • Light intensity,
  • pH,
  • Salinity
• Conformers’ internal environment is dependent on the external environment, they have to live in stable environments.
• Advantage of being a conformer:

  • Low metabolic costs- not wasting energy on sweating etc.

  Disadvantages:

  • Less adaptable to environmental change
• Behavioural responses in conformers include basking in the sun or burrying in the sand to maintain optimum metabolic rate.
• Regulators control their internal environment using physiological mechanisms. Their internal environment is independent on the external environment
• Advantage of being a regulator:

  • Can live in a wider range of niches.

  Disadvantage of being a regulator:

  • Higher metabolic costs because homeostasis (physiological mechanisms) requires energy.
• Thermoregulation is the regulation if internal body temperature
• The hypothalamus in the brain sends electrical impulses through nerves to the effectors which returns temperature back to normal, this is negative feedback control.
• Ensuring temperature regulation is important so enzymes can work at their optimal.
• Sweat created a thin layer of moisture on the surface of the skin for heat to evaporate off of releasing heat from the body.
• When we’re too hot the hair erectors relax and lie flat against the skin reducing insulation and allowing heat to escape.
• When we’re too cold the hair erector muscle contracts (goosebumps) and allowed a layer of air to be trapped and acts as an insulator.
• To remove heat from the blood, nerve impulses directs bloods vessels to dilate (vasodilation) which causes more blood flow to the surface of the skin allowing heat to radiate out
• When body temperature drops, nerve impulses cause blood vessels to becomes constricted (vasoconstriction) which limits the surface area of blood to the skin and reduced heat loss.
• Our muscles move uncontrollably to produce heat from friction