HNS - Peripheral Nervous System Flashcards
PNS consists of _____ primarily.
12 pairs of cranial nerves
31 pairs of spinal nerves
What do the motor nerves do?
Conduct impulses from the CNS to the effectors.
What do sensory nerves do?
Conducting impulses from the receptors to the CNS.
The motor nerves, connect to which two systems?
The autonomic nervous system and the somatic nervous system.
What does autonomic mean?
Refers to involuntary muscles.
What does the autonomic nervous system do?
Conducts impulses from the CNS to the involuntary muscles.
What does the somatic nervous system do?
Conducts impulses from the CNS to the voluntary muscles.
What does somatic refer to in this context?
Voluntary muscles.
Connected to the autonomic nervous system are which two methods of division?
- Sympathetic division
2. Parasympathetic division.
What does sympathetic division refer to / do?
It preps the body for fight or flight.
Remember : sympathetic - SHAME I GOTTA GO
What does parasympathetic division do?
Brings the body back to normal after sympathetic division aka back to the status quo.
What is the main function of the CNS?
Receiving nerve impulses from the effectors, interpreting that info, and transmitting it to the effectors for the desired response.
What is the brain enclosed by?
The skull, skin, and three cerebral membranes, namely Pia matter, Dura matter, and Arachnoid membrane.
What is the pia membrane?
The innermost membrane, wrapped tightly around the brain.
It is rich in blood cells and provides oxygen + nutrients in the CNS.
What is the Dura membrane?
The tough outermost layer, closest to the skull cavity and spinal canal.
What does the arachnoid membrane refer to?
The thin middle layer between the dura and pia matter.
What are the functions of cerebral fluid?
1- acts as a shock absorber 2- removes waste 3- supplies neurons with nutrients and oxygen 4- prevents neuron dehydration 5- maintains pressure around CNS
Cerebral fluid exists where?
In the space between the dura matte and the arachnoid membrane.
What are the functions of the peripheral nervous system?
- Conducting nerve impulses from the receptors to the CNS
- conducting nerve impulses from the CNS to the effectors
What relationship do the parasympathetic and sympathetic divisions have?
An antagonistic one.
