4.2.2 - Neurons Flashcards
What are neurons
Nerve cells
- the body’s communication system, they feature all around the body
What are the 3 types of neuron
- sensory
- motor
- relay
What is the role of sensory neurons
Found in receptors such as ears, eyes, tongue and skin
- they carry here impulses to the spinal chord and the brain
What is the role of a motor neuron
Found in the CNS
- control muscle movements
- when they are stimulated they send signals to the muscles which lead to movement,
What is the role of a relay neuron
Found between input and output/ response neurons
- they are found in the brain and spinal chord
- they allow other types of Enron’s to communicate with each other
What does the CNS consist of
- brain: decides what to do, and tells the body actions
- spinal chord: conveys messages to and from the brain
What are the functions of the nervous system
- controls the body
- takes info from the environment using sensory receptors then sends signals that encode this into the ows.
- the info is processed to work out an appropriate response in the CNS
-output signals are sent to muscles or glands to activate the response.
Where is the cerebellum and what’s its function
- sits at the back of the cerebrum
- controls motor skills
- coordinates muscles to allow precise movement
Where is the brain stem and what is its function
- located at the bottom of the brain and connects brain to rest of body
- regulates essential functions for life
Eg: breathing heartbeat swallowing etc..
Where is the cerebrum and what is its function
- largest part of the brain, and divides into 4 parts which all carry out separate functions
- the two hemispheres are caused by a split down the cerebrum
- each hemisphere communicates using the corpus callosum
What is the somatic nervous system
Transmits info to and from the senses and to and from the CNS to the outside world- carries sensory info to the brain where muscle responses are produced
- sensory receptors: carry info to the spinal chord and the brain
- motor pathways: allows the brain to control movement
What is the peripheral nervous system
Consists of all nerves that are outside of the CNS
- there are throw divisions: the somatic nervous system and the autonomic nervous system
What is the autonomic nervous system
- transmits info to and from the internal organs to sustain life
- plays an important part if homeostasis
- carries out actions without your conscious awareness
- made up of motor pathways:
Sympathetic system - increases bodily activity & parasympathetic system - decreases bodily activity
What is the sympathetic nervous system
- involved in the fight/flight response
- in a scary situation the sympathetic nervous system prepares you to stay and attack or to run away
- it does this by increasing bodily activity
What is the parasympathetic nervous system
- maintains normal bodily activity via homeostasis
- rest and digest
- acts as a break and reduces the activities of the body that have been increased by the sympathetic nervous system
