Nervous System Flashcards
What is the purpose of the nervous system
System that send signals around the body and lets people respond to what is around them
What does the central NS consist of
The brain spinal cord and neurons
Role of the brain in the central ns
Receives and process sensory information
Initiates responses
Stores memories
Generates thoughts and emotions
Role of the spinal cord with central NS
- passes signals between brain and PNS
- control reflex responses
What does peripheral NS do
Transit info to and from the central NS
What is the PNS consist of
Somatic nervous system
Automatic nervous system
Autonomic nervous system
- controls involuntary bodily processes
Eg digestion, heart rate, respiration
What is the autonomic NS divided into
Sympathetic ANS and parasympathetic ANS
Sympathetic ANS
Prepares the body for action and stress
Parasympathetic ANS
Calms the body and conserves energy
What is a neuron
A nerve cell, a basic building bloc of the nervous system
Motor neurons
- impulses movs from the CNS to the rest of he body to muscles
- multi polar - multiple branches of cell body
sensory neurons
- transmits impulses (messages) from PNS about stimuli external nd internal from sense receptor to CNS
- ## uni polar - 1 branch
Relay neurons
- Most common type in CNS, transmits impulses moves between sensory and motor neurons
- interest in for from sense receptors
- multi polar
- don’t have myelin sheath
Excitatory synapse EPSP
The neurotransmitter causes an excitatory post synaptic potential, which makes it more likely for action potential to occur will be generated in the post synaptic potential
Inhibitory synapse IPSP
The neurotransmitter causes an inhibitory post synaptic potential which makes it less likely that an action potential will be generated in the post synaptic neuron
Whta do neurons form with other neurons
1000 synapses
Describe the process of summation
Response of the post synaptic neuron depends on overall combined effect of all EPSP and IPSP
- more EPSP action potential will fire
- more IPSP action potential will not
Process of synaptic transmissions
- nerve impulse travels down the axon
- vesicles move to pre synaptic membrane
- neurotransmitter released into cleft
- neurotransmitter binds to receptors on post synaptic membrane
-EPSP or IPSP created - neurotransmitter released from receptors on the post-synaptic membrane back into the vesicles of the presynaptic neurons