Unit 3-Divisions Of The Nervous System And Neural Pathways Flashcards
What are the two main nervous systems in the body?
The central nervous system (CNS)and the peripheral nervous system (PNS).
What makes up the central nervous system?
The brain and the spinal cord
What makes up the peripheral nervous system?
The somatic and autonomic nervous system.
What makes up the autonomic nervous system?
The sympathetic and parasympathetic system.
What does the somatic nervous system contain?
Sensory and motor neurons.
What do sensory neurons do?
Sensory neurons take impulses from sense organs to the CNS.
What do motor neurons do?
Take impulses from the CNS to muscles and glands
What is the pathway of the somatic nerve?
Receptors (e.g. sense organs) ➡️ Sensory neurons ➡️ CNS ➡️ Motor neurons ➡️ effectors (e.g. muscles and glands).
Is the somatic nervous system voluntary or involuntary?
Voluntary meaning under the conscious control of the brain.
How do the parasympathetic and the sympathetic systems work with each other?
They work antagonistically which means that they affect many of the same structures but have the opposite effects on them.
What does the sympathetic system do generally?
It prepares the body for action (fight or flight).
What does the parasympathetic system do in general?
It rests and relaxes the body for rest and digest.
Is the autonomic nervous system voluntary or involuntary?
Involuntary meaning done without will or conscious control.
What is the antagonistic action of the sympathetic and parasympathetic systems on the effect of heart rate (and cardiac output)?
Sympathetic increases cardiac output. Parasympathetic decreases cardiac output.
What is the antagonistic action of the sympathetic and parasympathetic systems on the effect of breathing rate (and intake of air)?
Sympathetic increases intake of air. Parasympathetic decreases intake of air.
What is the antagonistic action of the sympathetic and parasympathetic systems on the effect of peristalsis?
Sympathetic decreases the rate of peristalsis.
Parasympathetic increases the rate of peristalsis.
What is the antagonistic action of the sympathetic and parasympathetic systems on the effect of the production of intestinal secretions?
Sympathetic decreases production of intestinal secretions.
Parasympathetic increases production of intestinal secretions.
What are neurons?
The cells of the nervous system.
What does converge mean?
To come together and meet at a common point.
Where do converging pathways occur?
Converging pathways occur where impulses from several neurons travel to one neuron.
What do converging neural pathways do?
Converging neural pathways increase the sensitivity to excitatory or inhibitory signals.
What is an example of a converging neural pathway?
An example is where the neurons from rods in the retina/eye converge - this increases sensitivity to low levels of light.
What does ‘fight or flight’ mean?
Preparation of the body to produce more energy.
What is the arrangement of neurons in a converging neural pathway?
Several neurons to one.
What does to diverge mean?
To branch out from a common point.
What happens in a diverging neural pathway?
Impulses from one neuron travel to several neurons, therefore affecting more than one destination at the same time.
What is an example of a diverging pathway?
The fine motor control in the fingers.
What does reverberation mean?
Reverberation means a sound that occurs repeatedly, as in an echo.
What happens in reverberating pathway and what does this allow to happen?
Neurons later in the pathway link with branching neurons, sending the impulse back through the pathway. This allows repeated simulation of the pathway.
What are reverberating pathways used in?
Repetitive activities such as breathing.
What are the 3 different parts of the brain?
The cerebral cortex, the limbic core and the central core.
