Neurons and Action Potential - Topic 1 Flashcards
What are neurons?
Neurons are the basic cells of the nervous system, and are fundamental in the operation of homeostasis
What 2 key components are within the nerve impulse?
- Action Potential (conduction with a neuron)
- Synaptic Transmission (communication between neurons)
What is the role of Dendrites?
Receive synaptic input from axons
With the sum total of dendritic inputs determining whether the neuron will fire an action potential
What is the role of Soma?
It is located where the nucleus lies and is where the neuron’s DNA is housed
Where proteins are made to be transported throughout the axon and dendrites
What is the role of the body in a neuron?
Contains genetic information
Maintains the neuron’s structure
and provides energy to drive activities
What is the role of the Axon?
The axon is a thin fiber that connects neurons (nerve cells) so that they can communicate
What is the role of the myelin sheath?
Allows electrical impulses to transmit quickly and efficiently along the nerve cells
If the myelin become damaged these impulses slow down
What is the role of the nodes of Ranvier?
These are gaps in the myelin sheath coating on the neural axon
The nodes of Ranvier allow for ions to diffuse in and out of the neuron, propagating the electrical signal down the axon
What is the role of the axon terminal?
The axon terminal is the site of neurotransmitter release
What is the role of the synapse?
Synapses connect neurons and help transmit information from one neuron to the next
What are sensory neurons?
Sensory neurons transmit information from sensory receptors to the central nervous system (CNS)
What are relay neurons?
Relay neurons (interneurons) transmit information within the CNS as part of the decision-making process
What are motor neurons?
Motor neurons transmit information form the CNS to effectors (muscles of glands), in order to initiate a response
Difference of dendrite between sensory and motor neurons?
Sensory - Longer and receive sensory input from the environment
Motor - Shorter and receive signals from the CNS or interneurons.
Difference of soma between sensory and motor neurons?
Sensory - located in the dorsal root ganglion of the spinal cord
Motor - located in the ventral horn of the spinal cord
Difference of body between sensory and motor neurons?
Sensory - located outside the CNS
Motor - located inside the CNS
Difference of axon between sensory and motor neurons?
Sensory - long axon that transmits sensory information to the CNS
Motor - long axon that transmits motor commands to effector organs
Difference of myelin sheath between sensory and motor neurons?
Sensory - produced by Schwann cells in the PNS
Motor - produced by oligodendrocytes in the CNS or Schwann cells PNS
Difference of nodes of ranvier between sensory and motor neurons?
Both allow for saltatory conduction
Difference of axon terminal between sensory and motor neurons?
Sensory - synapses with interneurons in the CNS
Motor - synapses with effector organs at neuromuscular junctions
Difference of synapses between sensory and motor neurons?
Sensory - transmits signals to interneurons or directly to motor neurons
Motor - transmits signals to muscles or glands to elicit a response
What is the pre-synaptic cell?
The neuron that has just undergone action potential to pass on a signal toward a synapse
What is the post-synaptic cell?
The cell receiving information from another neuron and transmits signals away from a synapse
What is a synaptic cleft/terminal?
An area at the end of the axon, where a neuron releases neuron transmitters
