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WorksheetsNeurons (Text & Quiz)
Total questions: 1
Worksheet time: 4hrs 10mins
How do neurons communicate to process sensory information?
Through chemical signals only
Through electrical signals only
Through electrochemical signals
Through mechanical signals
What is the primary function of neurons in the brain?
To provide structural support to the brain
To transmit electrical signals and process information
To store nutrients for brain cells
To protect the brain from infections
What are the three main components of a neuron?
Dendrites, nucleus, axon
Dendrites, soma, axon
Soma, nucleus, myelin sheath
Axon, synapse, terminal button
What is the main source of input for a neuron?
Axon
Soma
Dendrites
Myelin sheath
What is the function of the nucleus in a neuron?
To extend signals to other neurons
To direct protein synthesis and supply energy
To insulate the axon
To form synapses with other neurons
What is the role of the myelin sheath in a neuron?
To receive information from other neurons
To direct protein synthesis
To insulate the axon and allow rapid signal transmission
To form synapses with other neurons
What is a synapse?
The main source of input for a neuron
The place where the axon of one neuron comes in close contact with the dendrite of another neuron
The process that extends far away from the soma
The insulating substance covering the axon
What is the terminal button?
The main source of output for a neuron
The end of the axon that forms synapses with spines on the dendrites of neurons
The insulating substance covering the axon
The process that extends outward from the soma
What do synaptic vesicles package together?
Receptor sites
Neurotransmitters
Ion channels
Dendritic spines
Which type of neuron helps us receive information about the world around us?
Motor neurons
Sensory neurons
Interneurons
Multipolar neurons
What is the main function of motor neurons?
To process sensory input
To initiate movement and behavior
To relay information forward
To communicate body temperature
Which type of neuron is involved in sensory perception such as the perception of light in the retina of the eye?
Unipolar neurons
Bipolar neurons
Multipolar neurons
Pyramidal neurons
What is the characteristic feature of multipolar neurons?
They have one neurite (axon) and no dendrites
They have one axon and one dendrite
They have one axon and many dendrites
They have no axons and multiple dendrites
What is the primary function of oligodendroglia cells in the brain?
To digest debris of dead neurons
To form the myelin sheath around axons
To carry nutritional support from blood vessels to neurons
To regulate the ionic composition of the extracellular fluid
Which type of glia cells digest debris of dead neurons?
Oligodendroglia
Microglia
Astrocytes
Neurons
What is the resting membrane potential?
The state of a neuron when it is actively transmitting a signal
The state of a neuron when it is at rest
The process of forming the myelin sheath
The process of digesting dead neurons
What ions are found in the intracellular and extracellular fluid of neurons?
Sodium (Na+), potassium (K+), chloride (Cl-), and anions (A-)
Calcium (Ca2+), magnesium (Mg2+), phosphate (PO4-), and bicarbonate (HCO3-)
Hydrogen (H+), hydroxide (OH-), sulfate (SO4-), and nitrate (NO3-)
Iron (Fe2+), copper (Cu2+), zinc (Zn2+), and manganese (Mn2+)
What is the composition of the cell membrane in neurons?
A single layer of protein molecules
A lipid bilayer of fat molecules
A double layer of carbohydrate molecules
A triple layer of nucleic acid molecules
What allows particular ions to pass between the intracellular and extracellular fluid in neurons?
Synapses
Myelin sheaths
Ion channels
Dendrites
What is the force on molecules to move from areas of high concentration to areas of low concentration?
Electrostatic pressure
Diffusion
Equilibrium potential
Resting membrane potential
What is the force on two ions with similar charge to repel each other and the force of two ions with opposite charge to attract to one another?
Diffusion
Resting membrane potential
Electrostatic pressure
Equilibrium potential
What is the voltage called at which the force of diffusion is equal and opposite of the force of electrostatic pressure?
Resting membrane potential
Equilibrium potential
Diffusion potential
Electrostatic potential
What is the baseline electrical charge inside the cell compared with outside the cell referred to as?
Equilibrium potential
Diffusion potential
Resting membrane potential
Electrostatic potential
What is the approximate resting membrane potential of a neuron?
-70 mV
1.5 V
240 V
0 mV
What is the role of the sodium-potassium pump in the neuron?
To pump 3 Na+ ions into the cell and 2 K+ ions out of the cell
To pump 3 Na+ ions out of the cell and 2 K+ ions into the cell
To pump 2 Na+ ions into the cell and 3 K+ ions out of the cell
To pump 2 Na+ ions out of the cell and 3 K+ ions into the cell
What is an action potential?
A small, constant electrical current in the neuron
A large, transient electrical current conducted down the axon
A large, constant electrical current in the neuron
A small, transient electrical current conducted down the axon
What is meant by the term "depolarization" in the context of an action potential?
A change in the charge or potential of the cell from a more positive direction to a more negative direction
A change in the charge or potential of the cell from a more negative direction to a more positive direction
A change in the charge or potential of the cell that remains constant
A change in the charge or potential of the cell that fluctuates randomly
What is the specific membrane potential called that a neuron must reach to initiate an action potential?
Resting membrane potential
Inhibitory postsynaptic potential
Threshold of excitation
Depolarizing potential
What type of current causes the membrane potential to become more positive and closer to the threshold of excitation?
Hyperpolarizing current
Depolarizing current
Resting current
Inhibitory current
What is the typical value of the threshold of excitation?
-70 mV
-50 mV
-40 mV
-100 mV
What type of postsynaptic potential is caused by a hyperpolarizing current?
Excitatory postsynaptic potential (EPSP)
Inhibitory postsynaptic potential (IPSP)
Resting membrane potential
Depolarizing postsynaptic potential
What happens when two EPSPs occur at the same time in a neuron?
They cancel each other out
They sum and become a larger depolarization
They sum and become a larger hyperpolarization
They cause an action potential to stop
What type of ion channel opens when the cell becomes depolarized and reaches the threshold of excitation?
Voltage-dependent Na+ channel
Voltage-dependent K+ channel
Ligand-gated Cl- channel
Mechanically-gated Ca2+ channel
What happens to the Na+ channels when the inside of the cell becomes very positively charged?
They open
They close and become refractory
They remain open
They become permeable to K+
What ensures that the action potential can only move in one direction down the axon?
The refractory period
The depolarization phase
The hyperpolarization phase
The sodium-potassium pump
What occurs during the hyperpolarizing phase of the action potential?
Na+ channels open
K+ channels close
K+ channels open
Na+ channels become refractory
What is the role of the sodium-potassium pump during the action potential?
To push Na+ into the cell
To push K+ into the cell
To push Na+ out of the cell
To push K+ out of the cell
What are the gaps in the myelin sheaths called?
Nodes of Ranvier
Axon terminals
Synaptic clefts
Dendrites
What is the function of myelin in relation to the action potential?
It speeds up the process of the action potential
It slows down the process of the action potential
It stops the action potential
It reverses the action potential
What is the process called when the action potential actively jumps from node to node?
Continuous conduction
Saltatory conduction
Synaptic transmission
Reuptake
What triggers the release of neurotransmitters in the presynaptic terminal button?
Synaptic vesicles
Reuptake
Action potential
Enzymes
Which neurotransmitter is the main inhibitory neurotransmitter in the brain?
Glutamate
Dopamine
Serotonin
Gamma-aminobutyric acid (GABA)
What happens to a neurotransmitter that does not bind to receptors?
It is broken down and inactivated by enzymes or glial cells
It remains in the synaptic gap
It causes an action potential
It binds to another neuron
What is the process called when a neurotransmitter is taken back into the presynaptic terminal button?
Synaptic transmission
Reuptake
Saltatory conduction
Depolarization
What causes the membrane potential to become more positive and move towards the threshold of excitation?
Inhibitory postsynaptic potentials
Excitatory postsynaptic potentials
Diffusion
Ionotropic receptor
What causes the membrane potential to become more negative and move away from the threshold of excitation?
Excitatory postsynaptic potentials
Diffusion
Inhibitory postsynaptic potentials
Ion channels
What opens to allow ions to permeate the cell membrane under specific conditions?
Axon
Dendrite
Ionotropic receptor
Cell membrane
What is the resting membrane potential of a neuron?
Approximately -70 mV
Approximately +70 mV
Approximately -50 mV
Approximately +50 mV
What is the threshold of excitation?
The specific membrane potential that the neuron must reach to initiate an action potential.
The maximum potential a neuron can reach.
The potential at which a neuron stops firing.
The resting potential of a neuron.
