Neuroscience Chapter on Neurotransmitters

What is the primary function of neurotransmitters at excitatory synapses?

What happens when acetylcholine binds to its receptors on the postsynaptic cell?

What is the role of the presynaptic neurone in the chemical synapse?

Which neurotransmitter is an example of one that typically depolarizes the postsynaptic membrane?

What occurs in the postsynaptic cell if depolarization reaches the threshold?

What is the hallmark characteristic of an action potential?

What initiates the depolarization phase of an action potential?

What is the threshold potential at which an action potential is generated?

What happens after the peak of the action potential?

During the depolarization phase of an action potential, which ion influx is primarily responsible?

How does the membrane potential behave as an action potential propagates?

What causes the repolarization phase of the action potential?

What is the resting membrane potential typically around?

What is the role of voltage-gated slow calcium channels in action potentials?

What defines the absolute refractory period in action potentials?

What is the main role of voltage-gated potassium channels (VGPCs) during an action potential?

What occurs during the threshold potential of an action potential?

What is responsible for the repolarization of the membrane following an action potential?

Which of the following statements about action potentials is true?

What is the initial membrane potential before an action potential occurs?

Which ion's movement causes the membrane potential to reach +30 mV during an action potential?

What effect does hyperpolarization have on a neuron?

What is primarily responsible for the faster propagation of action potentials in myelinated neurons?

What is the role of the myelin sheath in neurons?

Where are voltage-gated sodium channels located in myelinated neurons?

Which of the following best describes the resting membrane potential?

What ion influx is primarily responsible for depolarization during an action potential?

Which neurotransmitter is involved in hyperpolarization at an inhibitory synapse?

What structural feature allows for muscle contraction in muscle fibers?

What happens when ACh binds to the closed ACh receptor?

Where are nicotinic receptors primarily located?

What type of receptor is the muscle-type nicotinic receptor?

What is the primary mechanism by which ACh is cleared from the synaptic cleft after its release?

What is the effect of nicotine on nicotinic receptors?

How does the binding of ACh affect the direction of the action potential (AP)?

What is a consequence of ACh remaining in the synaptic cleft for too long?

Which ion movement is primarily responsible for muscle contraction following ACh receptor activation?

What is the primary action of a neurotransmitter at an excitatory synapse?

Which of the following ions is primarily associated with the depolarization of the postsynaptic membrane when acetylcholine is released?

What must occur for an action potential to be generated in the postsynaptic cell?

How does the neurotransmitter affect the membrane potential of the postsynaptic cell?

In the context of the chemical synapse, what is the function of the synaptic cleft?

What is the main reason that action potentials can travel along the plasma membrane without diminishing?

How does the frequency of action potentials relate to the strength of a stimulus?

What is the effect of gamma aminobutyric acid (GABA) on the postsynaptic membrane?

During which phase of an action potential do sodium channels open due to positive feedback?

What characterizes the all-or-none principle of action potentials?

What ion movement primarily reverses the membrane potential during an action potential?

During which phase do voltage-gated potassium channels (VGPCs) primarily operate?

What happens after the closing of voltage-gated sodium channels (VGSCs)?

What is the refractoriness of a neuron primarily due to?

Which of the following best describes the role of threshold potential in action potentials?

What is the primary factor that restores resting membrane potential after depolarization?

What occurs if a neuron receives a stimulus during the relative refractory period?

Which ion's movement is responsible for the rapid depolarization phase of an action potential?

What effect would an acetylcholinesterase (AChE) inhibitor have on muscle contraction?

Which neurotransmitter is primarily responsible for muscle contractions in the somatic nervous system?

Where do the neurons that innervate skeletal muscles originate?

What type of control do the motor neurons in the somatic nervous system exert on skeletal muscles?

What effect do inhibitory postsynaptic potentials (IPSPs) have on motor neurons in the somatic nervous system?

Which of the following structures is involved in the higher control of muscle activity?

What kind of innervation do skeletal muscles receive from motor neurons in the somatic nervous system?

What occurs when acetylcholine is released at the effector organ during neuromuscular transmission?

What is the primary distinction between the autonomic nervous system and the sensory-somatic nervous system?

Which type of neuron is responsible for transmitting information from the central nervous system (CNS) to effectors like muscles?

What best defines a neurotransmitter?

During neurotransmission, what happens after acetylcholine (ACh) is released into the synaptic cleft?

What is the role of acetylcholinesterase in the neuromuscular junction?

Which of the following is characteristic of nicotinic receptors at the neuromuscular junction?

Which term describes the neurones that carry signals towards the central nervous system?

What is the primary function of dendrites in a neuron?

What characterizes the structure of bipolar neurons?

What role does the axon hillock play in a neuron?

What role does choline acetyltransferase play in the neurotransmitter acetylcholine synthesis?

What is the primary effect of the local current flow induced by the end-plate potential (EPP)?

How does the binding of acetylcholine affect the ion channels located in the motor end plate?

What occurs in the presynaptic terminal just before acetylcholine is released?

What structural change occurs to the motor neuron as it approaches the muscle cell?

Which event marks the initiation of the action potential?

What occurs to the membrane potential during the peak of an action potential?

How does the membrane potential return to its resting state after an action potential?

What characteristic of action potentials allows them to propagate without losing strength?

During the action potential, what is the immediate effect of voltage-gated sodium channel opening?

What happens to the voltage-gated sodium channels during the repolarization phase of an action potential?

What is the result of potassium ions moving out of the cell during the action potential?

What does the term 'threshold potential' refer to in the context of action potentials?

What effect does hyperpolarization have on the ability of a neuron to generate an action potential?

Which feature of myelinated neurons facilitates faster action potential propagation?

What occurs at the nodes of Ranvier during the action potential propagation in myelinated neurons?

What is the primary role of the GABA receptor in inhibitory synapses?

What characterizes the membrane potential during resting state in a neuron?

How does myelin affect current flow in neurons?

Which of the following ions primarily influences hyperpolarization in a postsynaptic neuron?

What structural adaptation of muscle fibers enables effective contraction?

What is the primary function of nicotinic ACh receptors at the neuromuscular junction?

Which of the following accurately describes the process by which ACh is cleared from the synaptic cleft?

In the context of the action potential, what does the opening of voltage-gated sodium channels (VGSCs) signify?

What role do nicotinic receptors play in the central nervous system?

What effect does prolonged presence of ACh in the synaptic cleft have on muscle function?

Which statement accurately describes ionotropic receptors like nicotinic receptors?

During excitation-contraction coupling, which ion's release is crucial for muscle contraction?

How does nicotine interact with nicotinic receptors?

What is the primary function of the T-tubes in skeletal muscle?

What is formed when a motor neuron terminates its connection with a skeletal muscle fiber?

Which characteristic is true regarding the axons of motor neurons innervating skeletal muscle?

What effect do miniature end plate potentials (mEPP) have on skeletal muscle fibers?

Which statement correctly describes the synaptic boutons at the neuromuscular junction?

What happens at the postsynaptic junctional folds of a muscle fiber?

What distinguishes the neuromuscular junction from other types of synapses?

What role does the autonomic nervous system play in relation to skeletal muscle?