Thermoregulation in Ectotherms

• All animals, except birds and mammals are ectotherms; obtain body heat from external environment, do not generate large amounts inside the body so use behavioural mechanisms to control body temperature
• Advantages: Use less food in respiration; so need to find less food; can survive for long periods without eating and more energy from food is used for growth
• Disadvantages: Less active in cooler temperatures; need to warm up in the morning to be active,so greater risk of predation and may need energy stores to survive winter without eating
• Behavioural Responses

  A) sun

  B) warm

  C) radiation

  D) conduction

  E) sun

  F) larger

  G) absorption

  H) less

  I) less

  J) sun

  K) burrow

  L) reduces

  M) sun

  N) body shape

  O) rib cage

  P) more

  Q) less

  R) sun

  S) increased

  T) more