Neurons & Nerve Impulses
The basic unit of the nervous system that conducts impulses
The neuron
The largest part of the brain, responsible for learning and reasoning
The Cerebrum
The brain and spinal cord make up this major division
Central Nervous System (CNS)
The somatic system controls what types of movement
Voluntary
A reflex is an example of this kind of response
Involuntary
Chemical messages that cross synapses
Neurotransmitters
This part of the neuron receives incoming signals from other cells
Dendrites
This brain region coordinates posture and balance
Cerebellum
The PNS is divided into what two main subdivisions?
Sensory (afferent) and Motor (efferent)
The autonomic system controls these types of muscles
Smooth and cardiac muscles
nociceptor
The space between neurons
Synaptic cleft
The fatty layer that speeds up impulse transmission along an axon
Myelin sheath
Occipital lobe
This part of the PNS carries signals to the brain
Sensory (afferent) neurons
This neurotransmitter causes skeletal muscle contraction
List the 5 components of a reflex arc
Receptor, Sensory neuron, Integration center, Motor neuron, Effector
This neurotransmitter is released by the sympathetic nervous system
Norepinephrine (NE)
What direction does an impulse travel through a neuron?
Dendrite --> Cell body -->Axon terminal
Controls the automatic functions like breathing and heartbeat
Brainstem
Nerves that connect the brain to the head and neck are called _________ nerves
Cranial nerves
The sympathetic division prepares your body for this kind of response
Fight or flight
Acquired reflex
Inhibitory neurotransmitters make the next neuron ______ likely to fire
less
These gaps between myelinated sections of an axon allow faster conduction
Nodes of Ranvier
Surface of cerebrum that increases surface area for activity
Cerebral cortex
The spinal cord connects the brain to the PNS and is protected by what bones?
Vertebrae
How do the sympathetic and parasympathetic divisions work together
They are antagonistic but maintain balance (homeostasis)
Type of receptor that responds to changes in temperature
Neurotransmitters act locally; hormones act through the bloodstream