Neuronal Transmission & Reflexes Quiz

<p>The membrane potential becomes less negative than the resting potential (B)</p> Signup and view all the answers

<p>They can vary in magnitude and duration. (D)</p> Signup and view all the answers

<p>Both sodium and potassium ions contribute to the creation of action potentials (D)</p> Signup and view all the answers

<p>Action potentials (A)</p> Signup and view all the answers

<p>It is less than the resting potential by approximately 15 mV. (B)</p> Signup and view all the answers

<p>Neurotransmitters are released to propagate signals across synapses (B)</p> Signup and view all the answers

<p>Graded potential (D)</p> Signup and view all the answers

<p>After-hyperpolarization (C)</p> Signup and view all the answers

<p>A neural pathway that controls a reflex action via sensory and motor neurons (B)</p> Signup and view all the answers

<p>Presence of negatively charged proteins (A)</p> Signup and view all the answers

<p>Leak channels (A)</p> Signup and view all the answers

<p>Lower concentration of Na+ outside the cell compared to inside. (D)</p> Signup and view all the answers

<p>The membrane potential becomes positive. (C)</p> Signup and view all the answers

<p>The overall charge balance extends to both intracellular and extracellular compartments (D)</p> Signup and view all the answers

<p>Pumps (C)</p> Signup and view all the answers

<p>The membrane potential becomes more negative again after depolarization (D)</p> Signup and view all the answers

<p>Anions cannot diffuse due to being fixed within the cell. (C)</p> Signup and view all the answers

<p>It follows an all-or-none principle. (D)</p> Signup and view all the answers

<p>Its magnitude decreases with distance from the stimulus site (B)</p> Signup and view all the answers

<p>To control the flow of ions based on specific signals. (B)</p> Signup and view all the answers

<p>The membrane potential returns to a more negative state. (B)</p> Signup and view all the answers

<p>Voltage-gated Na+ channels open quickly. (A)</p> Signup and view all the answers

<p>After-hyperpolarization phase. (B)</p> Signup and view all the answers

<p>During the after-hyperpolarization phase. (A)</p> Signup and view all the answers

<p>Opening of voltage-gated K+ channels. (B)</p> Signup and view all the answers

<p>Refractory period. (C)</p> Signup and view all the answers

<p>Decreased leak of current (D)</p> Signup and view all the answers

<p>Saltatory conduction (D)</p> Signup and view all the answers

<p>Voltage-gated Na+ channels (D)</p> Signup and view all the answers

<p>Only site where action potentials are evoked (A)</p> Signup and view all the answers

<p>Opening of non-selective cation channels (B)</p> Signup and view all the answers

<p>-70 mV (D)</p> Signup and view all the answers

<p>EPSP and IPSP can cancel each other out in synaptic integration. (B)</p> Signup and view all the answers

<p>Neurotransmitter receptors (B)</p> Signup and view all the answers

<p>Excitatory postsynaptic potential (EPSP) (B)</p> Signup and view all the answers

<p>Acetylcholine (A)</p> Signup and view all the answers

<p>Influx of Cl− (A)</p> Signup and view all the answers

<p>Causes explosive release of acetylcholine (D)</p> Signup and view all the answers

<p>Depolarization (D)</p> Signup and view all the answers

<p>Cell body (C)</p> Signup and view all the answers

<p>Parkinson's Disease (B)</p> Signup and view all the answers

<p>An automatic response to a stimulus (A)</p> Signup and view all the answers

The voltage difference between the inside and outside of a cell membrane when the cell is at rest.

A change in membrane potential that makes the inside of the cell less negative.

The process of generating and propagating an action potential through the ion channels of the cell membrane.

The difference in electrical charge across the cell membrane.

The fluid outside the cell.

The fluid inside the cell.

A local change in the membrane potential that varies in size.

A rapid and significant change in membrane potential that propagates along a nerve or muscle cell.

A protein that actively transports sodium ions out and potassium ions into a cell, contributing to maintaining the resting membrane potential.

A local change in membrane potential that varies in size and duration according to the stimulus strength (local signal).

A type of graded potential produced by sensory receptors in response to stimuli.

A type of graded potential that occurs in response to neurotransmitters at the synapse.

Differences in ion concentrations between the inside and outside of a cell are crucial for establishing and maintaining the resting membrane potential.

Plasma membrane channel proteins whose permeability to ions changes in response to the membrane potential.

The stable electrical charge across a cell membrane when it's not firing an action potential.

The membrane voltage at which an action potential is triggered.

A rapid, large change in membrane potential, travelling down the axon.

A phase where the membrane potential becomes more negative than its resting state, following repolarization.

Part of an action potential where the membrane potential becomes positive

The phase after repolarization where the membrane potential dips below the resting potential.

How electrical signals travel along neurons, using both passive and active current flow.

Adding up EPSPs (excitatory) or IPSPs (inhibitory) from repeated signals at a rapid rate.

Adding up EPSPs or IPSPs from different synaptic inputs.

Nerve fibers with a fatty coating (myelin), speeding up action potential transmission.

Action potentials "jumping" between gaps (nodes of Ranvier) in myelinated fibers.

Action potentials are generated by the movement of ions (Na+ and K+) through voltage-gated channels.

The stable electrical difference across a neuron's membrane when it's not transmitting a signal.

The minimum level of depolarization required to trigger an action potential (AP).

These channels open quickly during depolarization, allowing a massive influx of Na+ ions into the cell, causing the rapid rise of the AP.

The phase where the membrane potential returns to its resting state after the AP peak.

The phase where the membrane potential dips below the resting membrane potential.

A period during and after an AP when it is difficult or impossible to generate another AP.

Chemical messengers released from presynaptic neurons that excite or inhibit postsynaptic neurons. They are synthesized in the cytoplasm of the cell body and stored in vesicles in axon terminals.

Excitatory Postsynaptic Potential. A depolarizing change in the postsynaptic membrane potential that makes it more likely for the neuron to fire an action potential.

Inhibitory Postsynaptic Potential. A hyperpolarizing change in the postsynaptic membrane potential that makes it less likely for the neuron to fire an action potential.

An influx of Na+ (sodium) ions into the postsynaptic neuron. This means sodium ions move into the cell, making the inside more positive.

An influx of Cl- (chloride) ions or efflux of K+ (potassium) ions from the postsynaptic neuron.

A neurological disorder characterized by dopamine deficiency in the basal nuclei. This leads to tremors, rigidity, and slow movements.

A neurodegenerative disease characterized by acetylcholine deficiency. This leads to memory loss, confusion, and impaired thinking.

A rapid, automatic (involuntary) response to a stimulus, such as a pinprick. Reflexes are important for defending against harmful stimuli and maintaining body support.