4.3 HY Organization of the Human Nervous System Flashcards
What are some things that the nervous system regulates that you don’t think of?
Regulation of endocrine organs.
Exocrine glands.
How are sensory neurons, motor neurons, efferent neurons, and afferent neurons related?
Sensory Neurons= afferent, towards the CNS
Motor neurons= efferent, away from the CNS
This is the opposite of what I think, it is NOT Afferent= away
What are interneurons?
They are found between other neurons
They are the most numerous type.
Linked to reflexive behavior.
What part of the spinal cord do the sensory neurons travel?
What about motor neurons?
The dorsal root ganglia. In the back
Motor neurons travel ventrally.
What’s the difference in motor neurons between the somatic and autonomic nervous system?
Somatic Nervous System=There is no synapse, there is only one neuron.
Autonomic (para and sympathetic)= two neurons work in series to transmit messages in the spinal cord. The preganglionic neuron (CNS) and the post-ganglionic neuron (PNS).
What is the main role of the parasympathetic nervous system?
To conserve energy.
What nerve of the parasympathetic system is responsible for parasympathetic innervation in the abdominal cavity?
The Vagus Nerve (CN X/10)
Tell me what the parasympathetic nerve does on the following organs:
Pupils:
Mouth:
Bronchi:
Heart Rate:
Liver (x2):
Adrenal Glands:
Gut:
Bladder:
Penis:
Pupils: constriction
Mouth: salvation
Bronchi: constricts bronchi
Heart Rate: decreases rate
Liver (x2): inhibits glucose release, stimulates bile
Adrenal Glands: Inhibits adrenaline production
Gut: Stimulates peristalsis and secretion
Bladder: Contracts bladder
Penis: erection
What is the neurotransmitter that is released by the parasympathetic nervous system and associated ganglions?
Acetylcholine is the neurotransmitter responsible for the parasympathetic responses in the body and is released by both preganglionic and post-ganglionic neurons.
What neurotransmitter is released by the sympathetic nervous system and in what ganglions?
Preganglionic neurons release acetylcholine
Most post-ganglionic neurons release norepinephrine.
What are reflex Arcs?
What are the two types of reflex arcs?
Neural circuits that control reflexive behavior, and connect interneurons, without the need to send the original information to the brain before giving a motor response.
Two types: Monosynaptic, and polysynaptic.
What is a monosynaptic reflex arc?
What is an example?
There is only a single synapse between the sensory neuron that receives the stimulus and the motor neuron that responds to it.
Knee jerk reflex is an example. This is a protective reflex. Because when it is stretched, in order to prevent tearing, the quadriceps need to contract.
What is a polysynaptic reflex arc?
What’s an example of this?
There is at least one interneuron between the sensory and motor neurons.
An example of this is the Withdrawal reflex, such as if you step on a nail, there are multiple muscles that pull it away. This requires more than one arc, because if you jerk one leg back, you automatically need to compensate with the other leg.
