The divisions of the nervous system

Question 1

what is the nervous system??

Answer 1

• a highly specialised set of cells in the human body and is our primary internal communication system.
  -Made up of billions neurons
• brain is the information processor and centre part of the system and is the most complicated structure

Question 2

what is the structure of the nervous system?

Answer 2

The nervous system =
- CNS = spinal cord + brain
- PNS = somatic + automic = parasympathetic branch and sympathetic branch

Question 3

What is the CNS?

Answer 3

• is comprised of the brain and spinal cord and it is a highly organised system
• has two main structures which are the brain and the spinal cord

Question 4

what does the brain do in the CNS?

Answer 4

• two main functions = collect, process and respond to info from environment
  to coordinate and direct the working of different organs and cells within the body
• its vital role is to ensure life is maintained
• many parts of brain which some are more primitive and invoved in vital funcctioning like heart beat.
  other areas are higher order thinking such as planning and problem solving - prefrontal cortex

Question 5

what does the spinal cord do in the CNS?

Answer 5

• carries messages to and from the brain to the PNS.
• relays info to and from brain to the rest of the body
• allows brain to monitor bodily processes like breathing and digestion and coordinate body movements.

Question 6

outline what is meant by an arc reflex?

Answer 6

• reflex arc is a special type of neural circuit that begins with a sensory neuron at a receptor and ends with a motor neuron at an effector
• there are five steps in order = sensor, sensory neuron, CNS, motor neuron and muscle

Question 7

what is the peripheral nervous system?

Answer 7

• known as all the nerves in our body outside our brain and our spinal cord.
• main function is to relay nerve impulses from the CNS to the rest of the body and from the body back to the CNS
• lots of sensory and motor neuron pathways allow the CNS to be aware of what is going on the outside world and in the body. allows CNS to control our response systems
• has two main parts = somatic and autonomic nervous system

Question 8

what is the somatic nervous system??

Answer 8

• responsible for carrying sensor and motor information to and from the spinal cord
• concerned with voulentary movement of sketeletal muscles
• function is to send info from receptor cells in the sense organs to the CNS
• recieves info from CNS that direct on how muscles react
• maintains communication between CNS and outside world
• consists of sensory receptors which carry info to the spinal cord and the brain, sensory pathways which transfer and recieve info from senses like visual from eyes to brain
• motor pathways which allow the brain to control movement
• motor (efferent) pathways which direct voulentary movement of skeletal muscles and control movements

Question 9

what is the autonomic nervous system??

Answer 9

• responsible for functions that keep the body in a stable state - homeostasis = controls heart rate and breathing
• many of its functions are automatic - require little or no concious thought
• control centre = top of brain stem - hypothalamaus and pituitary gland
• has two main divisions =
• sympathetic branch = prepares for fight or flight response when faced with threat
• parasympathetic branch = activated once the threat has passes and helps dampen down stress reponse
• their actions are mostly antagonistic

Question 10

what are the differences of the SNS and the ANS?

Answer 10

• ANS is invoulentary and SNS is voulentary
• SNS has both motor and sensory neurons but ANS only has motor neurons
• ANS controls internal organs/ glands but SNS controls skeletal muscles and movement
• control centre of SNS in motor and somatosensory cortex but the ANS is brain stem