Synapses and The Reflex Arc Flashcards
What is the synaptic cleft?
The synaptic cleft is the small gap between the presynaptic neuron and the postsynaptic neuron where neurotransmission occurs.
How do electrical impulses travel in neurons?
Electrical impulses, or action potentials, travel along the axon of a neuron.
What triggers the release of neurotransmitters?
The release of neurotransmitters is triggered when electrical impulses reach the axon terminal.
What are vesicles in the presynaptic neuron?
Vesicles are small membrane-bound sacs that store neurotransmitters.
What happens to neurotransmitters after they bind to receptors on the postsynaptic neuron?
Neurotransmitters are often broken down by enzymes or reabsorbed by the presynaptic neuron.For recycling
Why do impulses only travel in one direction?
Impulses travel in one direction due to the structure of neurons and the refractory period following an action potential.
What is a reflex arc?
A reflex arc is a neural pathway that mediates a reflex action.
What are the types of stimuli?
The types of stimuli include:
* Thermal: Changes in temperature.
* Light: Changes in light intensity.
* Mechanical: Physical pressure or distortion.
* Chemical: Changes in chemical composition.
* Electrical: Changes in electrical charge.
What are the three types of neurons?
- Sensory Neurons: Transmit sensory information from receptors to the CNS.
- Relay Neurons: Connect sensory neurons to motor neurons within the CNS.
- Motor Neurons: Carry signals from the CNS to muscles or glands.
What is the Dorsal Root?
The dorsal root is the part of a spinal nerve that contains sensory fibers.
What is the Dorsal Root Ganglion?
The dorsal root ganglion is a cluster of sensory neuron cell bodies located just outside the spinal cord.
What is the Ventral Root?
The ventral root is the part of a spinal nerve that contains motor fibers.
What is a Spinal Nerve?
A spinal nerve is a mixed nerve that contains both sensory and motor fibers.
What are myelinated nerve fibers?
Myelinated nerve fibers are axons that are covered with a myelin sheath.
What are unmyelinated nerve fibers?
Unmyelinated nerve fibers are axons that lack a myelin sheath.
Explain the reflex arc process.
The reflex arc process involves the following steps:
* A stimulus activates a sensory receptor.
* Sensory neurons transmit the signal to the spinal cord.
* Relay neurons process the information and connect to motor neurons.
* Motor neurons send signals to the muscles to initiate a response.
