Signal Transmission Across a Synapse
● The junction between two neurons or between a neuron and an effector is called
a synapse.
● Neurons are not directly connected but have a small gap between them called
the synaptic cleft.
● Signal transmission across a synapse involves the use of chemical messengers
called neurotransmitters.
Steps in Signal Transmission Across a Synapse:
Step 1: Ca2+ Ion Entry
● When an action potential reaches the synaptic terminal, Ca2+ ions diffuse into
the axon.
Step 2: Release of Neurotransmitters
● Ca2+ ions cause vesicles containing neurotransmitters to fuse with the
presynaptic membrane.
● The junction between two neurons or between a neuron and an effector is called
a synapse.
● Neurons are not directly connected but have a small gap between them called
the synaptic cleft.
● Signal transmission across a synapse involves the use of chemical messengers
called neurotransmitters.
Steps in Signal Transmission Across a Synapse:
Step 1: Ca2+ Ion Entry
● When an action potential reaches the synaptic terminal, Ca2+ ions diffuse into
the axon.
Step 2: Release of Neurotransmitters
● Ca2+ ions cause vesicles containing neurotransmitters to fuse with the
presynaptic membrane.
