, The Endocrine System
Positive & Negative Feedback
Positive :
Negative
:
memorise these
graphs
Vasodilation to decrease temperature
0
0
Vasoconstric tion to increase temperature
n ote :
thermoreceptors a re found in the
hypothalamus .
input receptor Coordinator effector response
skin receptor smooth muscle
temp to o
thermo in ar teries and
vasoconstric tion
cold
receptor hypothalamus ar terioles
skin receptor smooth muscle
temp too
thermo in ar teries and
not receptor hypothalamus ar terioles vasodilation
example of positive feedback :
depolarization
of negative feedback potential
:
example action
The Pancreas
endocrine system endocrine t i ss u e (excretion eg . hor mones)
Islet of Langerhans ( tissue)
✗ cells to blood
produce glucagon increase glucose
B ce lls
produce insulin to decrease blood glucose
ATP,
lower blood glucose Leads to decreased respiration , decreased leading to an
energy deficit .
Hypoglycaemia .
higher blood glucose Leads to an increase in wa te r
moving into blood
by osmosis because wa te r potential in blood i s lower so
cells
dehydrate .
Hyperglycemic .
I
insulin
tuecagon
Positive & Negative Feedback
Positive :
Negative
:
memorise these
graphs
Vasodilation to decrease temperature
0
0
Vasoconstric tion to increase temperature
n ote :
thermoreceptors a re found in the
hypothalamus .
input receptor Coordinator effector response
skin receptor smooth muscle
temp to o
thermo in ar teries and
vasoconstric tion
cold
receptor hypothalamus ar terioles
skin receptor smooth muscle
temp too
thermo in ar teries and
not receptor hypothalamus ar terioles vasodilation
example of positive feedback :
depolarization
of negative feedback potential
:
example action
The Pancreas
endocrine system endocrine t i ss u e (excretion eg . hor mones)
Islet of Langerhans ( tissue)
✗ cells to blood
produce glucagon increase glucose
B ce lls
produce insulin to decrease blood glucose
ATP,
lower blood glucose Leads to decreased respiration , decreased leading to an
energy deficit .
Hypoglycaemia .
higher blood glucose Leads to an increase in wa te r
moving into blood
by osmosis because wa te r potential in blood i s lower so
cells
dehydrate .
Hyperglycemic .
I
insulin
tuecagon
