What are the divisions of the nervous system
- Central nervous system- brain and spinal cord
- peripheral nervous system- sends information to cns via muscles and glands
- somatic nervous system- transmits information to cns from receptor cells- voluntary
- autonomic nervous system- transmits information to and from internal bodily organs and has two sub sections, sympathetic and parasympathetic- involuntary movements
What is the role of the central nervous system
Responsible for processing information and coordinating responses
Give the acronym for sympathetic and parasympathetic functions
S-salvation
L-lacrimation
U-urination
D-digestion
D-defecation
What is the role of the pituitary glands
Controls release of hormones from most other endocrine glands in the body
How does the body go from a parasympathetic state to sympathetic state
-body perceives threat and sensory information is released into the brain
-hypothalamus signals sympathetic nervous system to activate
-adrenal medulla release adrenaline to prepare body for flight or fight response
-results in physiological changes and heightened alertness
What are the symptoms of being in the sympathetic state
Increased heart rate, dilated pupils, increased blood pressure, reduced salivary flow, slow digestion, shallow breathing, glycogen is released from liver providing energy
What are the three different neurons and their roles
Sensory- transmits sensory information from receptors to the cns
Relay- connects sensory neurons to motor neurons and processes information within the cns
Motor- carries commands from the cns to the muscle or glands to produce movement or secretion
What are the first 3 steps of synaptic transmission
- Action potential travels down axon of presynaptic neuron and reaches axon terminal
- arrival of action potential causes voltage gated calcium channels to open in the presynaptic membrane - calcium ions then flood into the presynaptic neuron due to concentration gradient
- Influx of calcium ions triggers synaptic vesicles containing neurotransmitters to move towards and fuse with presynaptic membrane
What are the last 3 steps of synaptic transmission
- Fusion of vesicles with presynaptic membrane caused neurotransmitters to be released into the synaptic cleft via exocytosis
- Neurotransmitters diffuse across synaptic cleft and bind to specific receptors on postsynaphic neuron’s membrane
- If neurotransmitter causes opening of sodium channels it results in an excitatory post synaptic potential- increasing likelihood of action potential in post synaptic neuron- causes opening of chloride or potassium- inhibitory postsynaptic potential- decreases likelihood of action potential
