Mastering Synaptic Transmission and Excitable Tissue Functions

Dr. Mike explains synaptic transmission, where neurons communicate with excitable tissues like muscles and glands. He covers resting membrane potential, action potentials, and the role of voltage-gated sodium and calcium channels. The video details how neurotransmitters are released and their excitatory or inhibitory effects on target tissues, ultimately triggering or inhibiting action potentials.

What is the primary function of synaptic transmission?

• To transmit signals within a single neuron

• To facilitate communication between neurons and excitable tissues

• To generate electrical impulses in muscles

• To store information in the brain

Which of the following best describes the resting membrane potential?

• Negative inside and positive outside the cell

• Positive inside and outside the cell

• Positive inside and negative outside the cell

• Equal charge inside and outside the cell

What triggers the opening of voltage-gated sodium channels during an action potential?

• An increase in internal potassium concentration

• A decrease in external calcium concentration

• A change in voltage across the membrane

• The presence of neurotransmitters

What happens when an action potential reaches the axon terminal?

• The neuron becomes hyperpolarized

• Voltage-gated calcium channels open

• Voltage-gated sodium channels open

• Neurotransmitters are synthesized

What role does calcium play at the synaptic terminal?

• It triggers the fusion of vesicles with the cell membrane

• It inhibits neurotransmitter release

• It closes voltage-gated sodium channels

• It depolarizes the postsynaptic cell

How do excitatory neurotransmitters affect the postsynaptic cell?

• They open potassium channels

• They open sodium or calcium channels

• They decrease the cell's membrane potential

• They close chloride channels

Which neurotransmitter is typically excitatory in muscle tissue?

• GABA

• Dopamine

• Serotonin

• Acetylcholine

What is the effect of inhibitory neurotransmitters on the postsynaptic cell?

• They make the inside of the cell more negative

• They increase the likelihood of an action potential

• They cause the cell to secrete substances

• They open sodium channels

Which ion movement is associated with inhibitory neurotransmitters?

• Chloride ions moving out of the cell

• Calcium ions moving into the cell

• Potassium ions moving out of the cell

• Sodium ions moving into the cell

What is an example of an inhibitory neurotransmitter?

• Serotonin

• GABA

• Glutamate

• Acetylcholine