nervous system: specialised network of cells that is our primaryinternalcommunication system - based on electrical and chemical signals
main functions:
to collect,process and respond to information
to co-ordinate the work of different organs and cells
central nervous system: made up of brain and spinal chord
brain: centre of all conscious awareness - out layer (cerebral cortex) covers the brain like an orange peel
highly developed in humans and is what distinguishes our mental functions
spinal chord: passes messages to and from the brain, connecting nerves to the PNS
also responsible for reflex actions - pulling hand away from a hot plate
peripheral nervous system: transmits messages through millions of neurons to and from the central nervous system
autonomic nervous system (ANS) : governs vital functions in the body - breathing, heart ratre
somatic nervous system (SNS): governs muscle movement and receives information from sensory receptors
endocrine system: controls vital functions in the body
thyroid gland: produces hormones that are secreted into the bloodstream and can affect any cell that has a receptor
thyroid gland produces thyroxine, affecting cells in the heart
pituitary gland: 'master gland' as it controls the release of hormones from all other glands
glands
adrenal
ovaries
testes
pancreas
endocrine and autonomic work together during a stressful event.
during event:
hypothalamus activates pituitary gland to trigger activity in sympathetic branch
this then changes the parasympathetic state to the sympathetic state
adrenaline: stress hormone that is released into the bloodstream - triggers physiological changes in the body that create physiological arousal, ready for fight or flight
parasympathetic action: once the threat has passed, the nervous system returns the body to its resting state
parasympathetic system acts as a 'brake' and reduces the activities of the body that were increased due to the threat