3.1 Flashcards
What structure are in the central nervous system (CNS)?
brain and spinal cord
What is function of the brain?
to process information
What is the function of the spinal cord?
connects the brain with peripheral nervous system
What structure are in the peripheral nervous system (PNS)?
peripheral nerves
How can the peripheral nervous system be further sub-divided?
Somatic nervous system (SNS) and autonomic nervous system (ANS).
The autonomic nervous system can be divided into sympathetic and parasympathetic.
What is the role of the somatic nervous system?
The somatic nervous system is a component of the peripheral nervous system that is in control of voluntary movements and transmits and receives sensory signals.
- responsible of bringing about certain involuntary reflex actions but most of the control that it exerts is over voluntary movements of skeletal muscles
What is the role of the autonomic nervous system?
The autonomic nervous system is a component of the peripheral nervous system that is in control of autonomic movements and physiological processes, like controlling heart rate and peristalsis.
What actions do the autonomic nervous system control?
- control of heart rate
- breathing rate
- release of intestinal secretions
What is the difference between the sympathetic and parasympathetic nervous system?
The sympathetic and parasympathetic nervous systems are antagonistic branches of the autonomic nervous system.
The sympathetic nervous system initiates the ‘fight or flight’ response in the body, increasing energy expenditure.
The parasympathetic nervous system initiates the ‘rest and digest’ state in the body, slowing the rate of energy expenditure.
How do the sympathetic and parasympathetic systems affect the heart?
Sympathetic - increases heart rate
Parasympathetic - decreases heart rate
How do the sympathetic and parasympathetic systems affect the lungs?
Sympathetic - increases breathing rate
Parasympathetic - decreases breathing rate
How do the sympathetic and parasympathetic systems affect peristalsis?
Sympathetic - decreases amount of contractions in the gut, slowing the rate of peristalsis
Parasympathetic - increases the amount of contractions in the gut, increasing the rate of peristalsis.
In neural pathways, what are receptors?
Receptors are protein that receive a signal and transmits the signal to bring about a response.
In neural pathways, what are effectors?
Effectors are cells or tissues that respond to a nerve signal.
From stimulus to response, summarise each step of a neural pathway
stimulus - receptor - sensory neuron - inter neuron - motor neuron - effector - response
What does converge mean?
to come together and meet at a common point
Decribe the structure of converging pathways
Converging pathways involve signals from multiple neurons converging at one neuron
How do converging pathways function?
Converging pathways increase the sensitivity of signals by amplifying an excitatory or inhibitory signal.
Describe one example of a converging neural pathway
the rods in the retina, so increasing sensitivity to low levels of illumination through summation
What does diverge mean?
to branch out from a common point
Describe the structure of diverging pathways
Diverging pathways involve one neuron transmitting signals to multiple neurons.
How do diverging pathways function?
Diverging pathways allow a signal to affect multiple locations at the same time.
Describe one example of a diverging neural pathway
motor neurons allows fine motor control of the fingers
What does reverberating mean?
a sound that occurs repeatedly, as in an echo or a vibrating tuning fork.
Describe the structure of reverberating pathways?
Reverberating pathways involve neurons further down the pathways transmitting signals to those further up the pathway, to travel down again.
How do reverberating pathways function?
Reverberating pathways are used in repetitive actions as the signal is repeated over and over.
What are sensory neurons?
nerve cells which carry nervous impulses from sense organs to the CNS
What are motor neurons?
nerve cells which carry nervous impulses from the CNS to muscles and glands
What do sympathetic fibres act as?
they act as accelerators and if they gain an upper hand, the body is prepared for action by processes that ensure an increased supply of oxygen to the muscles.
What do parasympathetic fibres act as?
they act as breaks on activity and when they gain the upper hand, the body is able to rest and perform activities such as the breakdown of food.
