Microtubule Presvnaptic Presynaptic neuron Cytoplasm neuron Synaptic vesicle Mitochondrion ○○ Gar neuron junction lons flow through gap junction channels Synaptic Neurotransmitter released Presynaptic membrane icle fusing Presynaptic membrane S cleft 。 Postsynaptic neurotransmitter membrane Gap junction channels Postsynaptic receptor lons flow through membrane postsynaptic channels Electrical Synapse Chemical synapse Purves 2001
Electrical Synapse Chemical Synapse Purves, 2001
II The Chemical Synapse and Signal Transmission
II The Chemical Synapse and Signal Transmission
lI The Chemical Synapse and signal Transmission ● The chemical Synapse specialized junction that transfers nerve Transmitter vesicles Impulse information Mitochondria from a pre synaptic membrane to a Presynaptic terminal postsynaptic membrane using Receptor proteins neurotransmitters Synaptic cleft (200-300 and enzymes angstroms Soma of neuron
II The Chemical Synapse and Signal Transmission ⚫ The chemical synapse – specialized junction that transfers nerve impulse information from a pre synaptic membrane to a postsynaptic membrane using neurotransmitters and enzymes
Synaptic connections ~100,000,000,000 neurons in human brain Each neuron contacts 1000 cells How many synapses?
Synaptic connections • ~100,000,000,000 neurons in human brain • Each neuron contacts ~1000 cells • How many synapses?
Chemical Synapses Neurotransmitter- chemical intermediary Ca2+ Action Axon Ca2+potentials Action released from one otential Ca2+ neuron and influences Ca2+ Protein kinase activates Protein kinase (inactive) Calmodulin another Synaptic (inactive) vesicles phosphorylates synapsin Synaptic cleft- a small Docking proteins gap between the sending synaptic clet ca+. Fusion and (presynaptic) and the ex ocytosis CE Neurotransmitter. receiving(postsynaptic) released site Ca
• Neurotransmitterchemical intermediary released from one neuron and influences another • Synaptic cleft- a small gap between the sending (presynaptic) and the receiving (postsynaptic) site Chemical Synapses