thermoregulation validation

what is homeostasis?

the process by which the body maintains a relatively constant internal environment despite changes to the internal or external environment to ensure optimal body function

why is homeostasis important?

cells function best within a narrow range of conditions. homeostasis ensures conditions remain suitable for normal metabolism and enzyme activity.

what is a homeostatic set point?

the normal range that the body aims to maintain

what is a stimulus?

a detectable change in the internal or external environment

what is a receptor?

a specialised cell or organ that detects a stimulus

what is a modulator?

the organ that receives information from receptors and coordinates the appropriate response

what is an effector?

a muscle or gland that carries out response directed from modulator

what is negative feedback?

prevents conditions from moving too far away from normal range and helps maintain homeostasis

what is thermoregulation?

the maintenance of a relatively constant core body temperature

which part of the brain regulates body temperature?

the hypothalamus

what do thermoreceptors detect?

changes in body temperature

what happens to blood vessels in the skin when body temperature is too high?

they undergo vasodilation

how does vasodilation cool the body?

more blood flows close to the skin surface, increasing heat loss

why does sweating cool the body?

evaporation of sweat removes heat energy from the skin

what happens to blood vessels in the skin when body temperature is too low?

they undergo vasoconstriction

how does vasoconstriction reduce heat loss?

less blood reaches the skin surface, conserving heat

why does shivering increase body temperature?

rapid muscle contractions produce heat through respiration

what are structural adaptations for thermoregulation?

physical features that affect heat gain or loss such as fur, blubber and body size

give examples of behavioural thermoregulation

basking, seeking shade, burrowing, huddling

give examples of physiological thermoregulation

sweating, shivering, vasodilation, vasoconstriction

what is the difference between structural, behavioural and physiological mechanisms?

structural = physical features
behavioural = actions taken
physiological = internal body processes

what is an endothermic animal?

an animal that generates most of its body heat through internal metabolic processes

what is an ectothermic animal?

an animal that relies mainly on external heat sources to regulate its body temperature

give examples of endothermic animals

mammals and birds

give examples of ectothermic animals

reptiles and amphibians

how do endotherms maintain body temperature?

by producing heat internally through metabolism and using physiological mechanisms

how do ectotherms maintain body temperature?

mainly through behavioural strategies

what is one advantage of being an endotherm?

can remain active over wide range of environmental temperatures

what is one disadvantage of being an endotherm?

require large amount of energy (food) to maintain body temperature

what is one advantage of being an ectotherm?

require less food because they don’t use as much energy to maintain body temperature

what is one disadvantage of being an ectotherm?

activity level depends on environmental temperature so may become inactive when cold