The Nervous System Flashcards
What does the nervous system do?
Allows us to receive, process, perceive, & respond to information about our environment & our-self
What are the 2 main divisions of the nervous system & what do they correlate to?
- Central Nervous System (CNS)
- Brain
- Spinal cord - Peripheral Nervous System (PNS)
- nerves that run off the spinal cord
What are the brains 2 major functions?
- Control behavior
2. Regulate the body’s physiological response
How many neurons does the adult brain contain
About 100 billion neurons
What is the total percent of blood volume in ones head
There is 20%
What is a segment in the spinal cord?
- Bone (Vertebrate)
- Disk
- 2 nerves (L;R)
What is the first area of the spinal cord called & how many segments does it have?
- Cervical –> near neck
- 7 segments
What is the second area of the spinal cord called & how many segments does it have?
- Thoracic –> near shoulders & upper back
- 12 segments
What is the third area of the spinal cord called & how many segments does it have?
- Lumbar –> near lower back
- 5 segments
What is the fourth area of the spinal cord called
- Sacrum –> near tail bone
What is the fifth area of the spinal cord called
- Coccyx
What are the responses correlating to Peripheral
- Somatic (voluntary)
- Autonomic (involuntary)
What 2 things does autonomic (involuntary responses) lead to? (give examples for what they do)
- Sympathetic
- fight or flight
- mass discharge
- increased heart rate
- increased breathing
- increased blood pressure
- pupils dilate (get bigger)
- decreased digestion - Parasympathetic
- rest and digest
- shuts down systems/ slows systems down one at a time
- decreased heart rate
- decreased breathing
- decreased blood pressure
- pupils constrict (get smaller)
- increased digestion
