specialised network of cells - communicate through electrical + chemical signals
collect, process, respond to enviroment
CNS: brain (2 hemispheres, covered by cerebral cortex, highly developed) + spinal cord (connects brain to PNS - reflex actions)
PNS: messages through neurones to + from CNS, subsystems: ANS (automatic, governs vital function), SNS (somatic, muscle movement + info from sensory receptors)
endocrine system
glands + hormones:glands produce hormones secreted through bloodstream - effects cell with receptor for that hormone
pituitary gland = master gland
endocrine + ANS - fight of flight
stressor percieved
hypothalamus activates pituitary gland
triggers ANSsympathetic branch
ANS resting (parasympathetic -> physiologically aroused (sympathetic) state
adrenalin relased from medulla - increased heart + breathing rate
parasympathetic action - reversed to normal once threat passed