Quizlet 2

Electrical synapses communicate through:

• Chemical messengers

• Gap junctions

• Vesicles

• Metabotropic receptors

Chemical synapses transmit signals using:

• Gap junctions

• Neurotransmitters

• Voltage channels between axons

• ATP release

Which ion triggers neurotransmitter vesicle release?

• Sodium

• Calcium (Ca²⁺)

• Potassium

• Chloride

What is synaptotagmin?

• A vesicle-binding enzyme that destroys neurotransmitter

• A sodium channel on the presynaptic membrane

• A calcium sensor that triggers exocytosis of docked vesicles

• A SNARE protein that cleaves vesicles

What holds synaptic vesicles near the presynaptic membrane before release?

• Vesicle receptors

• Vesicle and membrane SNAREs

• Chloride channels

• Voltage-gated potassium gates

When calcium binds synaptotagmin, it causes:

• Vesicle recycling

• The vesicle to fuse with the membrane by changing its conformation

• Opening of potassium channels

• Neurotransmitter reuptake

Ionotropic receptors are characterized by:

• G-protein activation

• Second messenger cascades

• An ion channel that opens when bound by an agonist

• Slow, modulatory effects only

Metabotropic receptors function by:

• Directly opening ion channels

• Indirectly affecting channels through G-proteins and second messengers

• Fusing vesicles at the synaptic terminal

• Blocking neurotransmitter diffusion

Excitatory neurotransmitters cause:

• Hyperpolarization

• Depolarization

• Closure of sodium channels

• Inhibition of neurotransmitter release

Inhibitory neurotransmitters increase permeability to:

• Sodium

• Potassium and chloride

• Calcium

• Magnesium