coordinating response Flashcards
what is adenyl cyclase
intracellular enzyme activated by certain hormones which converts ATP to cyclic AMP.
cyclic AMP
secondary messenger released inside cells to activate a response
when is fight or flight stimulated
when threat to survival is detected
what type of behaviour in mammals is initiated when survival is threatened
physiological behaviours are initiated to prepare for activity
name some physiological behaviours in response to fight or flight
pupils dilate
metabolic rate increase
ventilation increase
arterioles near muscles dilate
what is the survival value of pupils dilate
more light can enter eyes, retina becomes more sensitive
what is the survival value of the metabolic rate increasing
faster rate of respiration, more glucose conversion to make ATP
what is the survival value of the ventilation rate increases
increase gaseous exchange so more oxygen enters the blood and supplies respiration
what is the role of the external receptors
detect external threat
what is the survival value of the arterioles near the muscles dilating
larger volume of blood is supplied to muscles
give an example of external receptors
eyes, ears, nose
what do internal receptors do
detect internal threats such as increase in blood pressure or pain
what part of the brain uses sensory input to coordinate a response
cerebrum
the first step of coordinating a response is?
input feeds sensory centres in the cerebrum
what happens once cerebrum has received input
cererbum stimulates hypothalamus if threat is detected
what happens after the cerebrum has stimulated the hypothalamus
the hypothalamys increases activity in the sympathetic nervous system and stimulates hormones from pituitary gland
in the sympathetic system, describe the length of the pre ganglionic neurones and the post ganglionic neurones
sympathetic
pre- short
post- long
at what times is the sympathetic system most active
active at times of stress
what is the neurotransmitter present in the sympathetic system
noradrenaline
what nervous system is the sympathetic nervous system part of
autonomic system
How come the hypothalamus stimulates the nervous sytem and the endocrine system
because there is a requirement for both a rapid response and prolonged response.
when the sympathetic system is stimulated, adrenaline is released. Where is it released from
Adrenal Medulla
what is the first messenger and second messenger used in the sympathetic response
adrenaline- first
cyclic AMP- second
what happens when adrenaline binds to receptors on the plasma membrane
adrenaline stimulates “G proteins” To activate Adenyl Cyclase
