Homeostasis
The maintenance of a constant internal environment within a living
organism irrespective of the external conditions.
Important so cells can function effectively.
Negative feedback
There is a set point which is the 'norm' at which a system operates.
Changes in temp, ph, solute potential still fluctuate.
I
evictionfrom
et point set point
Positive feedback
An effector increasing a change.
• Oxytocin stimulates the contraction
Receptors- monitor condition &
of the uterus at the end of
provides input to the control
pregnancy. Contractions stimulate
centre/coordinator
the production of more oxytocin.
Coordinator evaluate info &
• When skin is cut , the first stage of
provides output to effector.
clotting is that platelets adhere to
Effector makes a response to
the cut surface. They secrete
take away deviation.
signalling molecules, which attract
more platelets.
, The kidney
Amino acids cannot be stored and surplus amino are deaminated in the
mammalian liver.
Amine group removed from amino acid.
The removed amine group (NH ) is converted into ammonia (highly toxic).
Addition of CO2 urea is formed and transported in the blood plasma to the
kidneys.
Used removed by kidneys & excreted in the urine.
cortex
nothin
Bemis
eter medulla
Tough13005
Motogp
rotas
The maintenance of a constant internal environment within a living
organism irrespective of the external conditions.
Important so cells can function effectively.
Negative feedback
There is a set point which is the 'norm' at which a system operates.
Changes in temp, ph, solute potential still fluctuate.
I
evictionfrom
et point set point
Positive feedback
An effector increasing a change.
• Oxytocin stimulates the contraction
Receptors- monitor condition &
of the uterus at the end of
provides input to the control
pregnancy. Contractions stimulate
centre/coordinator
the production of more oxytocin.
Coordinator evaluate info &
• When skin is cut , the first stage of
provides output to effector.
clotting is that platelets adhere to
Effector makes a response to
the cut surface. They secrete
take away deviation.
signalling molecules, which attract
more platelets.
, The kidney
Amino acids cannot be stored and surplus amino are deaminated in the
mammalian liver.
Amine group removed from amino acid.
The removed amine group (NH ) is converted into ammonia (highly toxic).
Addition of CO2 urea is formed and transported in the blood plasma to the
kidneys.
Used removed by kidneys & excreted in the urine.
cortex
nothin
Bemis
eter medulla
Tough13005
Motogp
rotas
