Slides in this set

Slide 1

Preview of page 1

SSER Ltd.…read more

Slide 2

Preview of page 2

Thermoregulation is the process
whereby animals regulate
their body temperature
Maintenance of a constant body temperature allows for:
· Independence from fluctuating external conditions
· Optimal activity of enzymes and hence metabolic
Enzymes are extremely sensitive to changes in temperature;
high temperatures denature enzymes (with potentially lethal
effects) and low temperatures slow their activity
There are several consequences of reduced enzyme activity;
these include a slowing of the metabolic rate and activity
levels, reduced muscle activity and a slowing of development…read more

Slide 3

Preview of page 3

Endotherms and Ectotherms
Biologists classify animals into two
groups with respect to their
thermoregulatory mechanisms
Endotherms are animals that generate their heat from
internal metabolic activity, and are reliant principally on
complex physiological mechanisms for maintaining a
constant internal (core) temperature
Ectotherms are animals that gain their heat energy from the
external environment; they rely largely on structural
adaptations and behavioural mechanisms for control of their
body temperature; body temperature in this group tends to
fluctuate as environmental temperatures change, thereby
limiting the range of environments
exploited by ectotherms
Mammals and birds are endotherms; insects, reptiles and
many other animal groups are typical ectotherms…read more

Slide 4

Preview of page 4

Heat Balance Endotherms (mammals and
birds) maintain a constant body
in Endotherms temperature through
mechanisms aimed at balancing
their heat gains and heat losses
Radiation and Radiation, conduction
conduction from and convection to the
the environment environment
Muscle Evaporation
contraction of sweat
General metabolism Expiration and excretion…read more

Slide 5

Preview of page 5

Physiological mechanisms are Information transmitted to
responsible for the the voluntary centres of the
maintenance of a stable, brain initiates behavioural
internal or core temperature activity, aimed at making the
body feel more comfortable
Body extremities generally
display much lower
temperatures that fluctuate
with changes in the
environmental temperature
Temperature receptors in the
skin respond to changes in the
environmental temperature
and transmit impulses to both
the hypothalamus and the
voluntary centres of the brain
Information transmitted to the
hypothalamus from skin
receptors initiates physiological
mechanisms aimed at heat
gain or loss…read more

Slide 6

Preview of page 6

The skin plays a major role
in temperature control
epidermis malpighian granular
layer layer
dermis receptors
Adipose (Fat)
erector hair
muscle skin follicle
capillaries gland…read more

Slide 7

Preview of page 7
Preview of page 7

Slide 8

Preview of page 8
Preview of page 8

Slide 9

Preview of page 9
Preview of page 9

Slide 10

Preview of page 10
Preview of page 10


No comments have yet been made

Similar Biology resources:

See all Biology resources »