The nervous system Flashcards
what is the nervous system?
a specialised network of cells in the human body, which is our primary internal communication system
what are the two main functions of the nervous system?
to collect,process and respond to information in the environment
to co-ordinate the working of different organs and cells
what can the human nervous system be split into?
the peripheral nervous system
the central nervous system
what can the peripheral nervous system be split into?
autonomic nervous system and somatic nervous system
what can the autonomic nervous system be split into?
sympathetic nervous system
parasympathetic nervous system
what does the central nervous system consist of?
the brain and the spinal cord
what does the central nervous system do?
the brain is the centre of all conscious awareness
the brain’s outer layer, the cerebral cortex is highly developed in humans
the brain is divided into two hemispheres
the spinal cord is an extension of the brain,
and responsible for reflex actions
what does the peripheral nervous system do?
transmits messages by millions of neurons to and from the central nervous system
what does the somatic nervous system do? (an extension of the peripheral nervous system)
responsible for carrying sensory and motor information to and from the spinal cord
what does the autonomic nervous system do? (an extension of the peripheral nervous system)
governs vital functions in the body including breathing, heart rate, digestion, sexual arousal and stress responses
It is also split into the sympathetic nervous system and parasympathetic nervous system. Their actions are mostly antagonistic, and they usually work in opposition to each other
what does the sympathetic nervous system do?
slows digestion inhibits saliva production increases heart rate stimulates glucose production (liver) stimulates urination dilates pupils dilates bronchi in lungs 'Fight or Flight'
what does the parasympathetic nervous system do?
increases digestion increases salvia production decreases heart rate stimulates bile production (liver) inhibits urination constricts pupils constricts bronchi in lungs (Digest and Rest)
what can anxiety and fear be classed as?
a mechanism to protect the body from danger or harm
when the threat has passed, the parasympathetic nervous system kicks in, in order to return everything to normal
the constant shifting between these two keeps your body ready for your current situation
