Human Nervous System Flashcards
HNS branches into what?
CNS AND PNS
What is CNS made up of?
Brain
Spinal cord
What is the PNS made up of?
Somatic nervous system
Autonomic nervous system
What does the autonomic nervous system branch off into?
Sympathetic nervous system
Parasympathetic nervous system
How many pairs of spinal nerves do we have?
31
How many pairs of cranial nerves do we have?
12 pairs
What does the brain do?
Draws information together from all over the body and sends information back out to the body in response
What does the spinal cord contain?
Nerves that carry messages between the brain and body
What is the CNS?
Central processor of information and control centre for human behaviour
Where does the PNS branch out from?
The spinal cord
What is the PNS?
Web of nerves carrying information together and from the CNS to the rest of the body
What is the role of the CNS?
When the body receives information from the senses, the PNS sends it to the CNS
What does the brain process?
All the information from the senses and generates a response
Example of the CNS’ role?
Tap on the shoulder -> receptor nerves (part of the PNS) send the information to the CNS.
Information passes through the spinal cord and into the brain
Touch is processed-> brain generates response
What does the spinal cord send to the brain?
Receives and sends information to and from the brain
What does the spinal cord allow in terms of bodily processes?
Allows the brain to monitor/regulate bodily processes
What does the spinal cord connect to?
The spinal nerves which connect to muscles and glands
What does the spinal cord contain?
Circuit of nerves which allow reflexes to be performed
Role of the somatic nervous system?
Carry sensory information
Provide muscle responses
What 2 things does the somatic nervous system have and what are their roles?
Sensory receptors- carry information to spinal cord and brain
Motor pathways- allow brain to control movement
What does the somatic nervous system do regarding information?
Transmits information to and from the senses and to and from the CNS and the outside world
What does the autonomic nervous system do?
Transmits information to and from internal organs to sustain life (made up of motor pathways)
Homeostasis- carries out actions without conscious awareness
What 2 systems does the autonomic nervous system branch off into?
Sympathetic
Parasympathetic
Does sympathetic increase or decrease bodily activity?
Increases
Does parasympathetic increase or decrease bodily activity?
Decrease
What does sympathetic do?
Fight/flight response
Prepares you to stay (fight) or run away (flight)
E.g. pupils dilating, accelerating heart rate
What does parasympathetic do?
Maintains homeostasis
Reduces body activities that have been increased by the sympathetic
Slow heart rate
