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WorksheetsCBNS: 106-Summer 2025 Practice Final
Total questions: 64
Worksheet time: 32mins
Which scientist is credited with supporting the neuron doctrine?
Golgi
Cajal
Descartes
Galvani
The term 'equilibrium potential' refers to:
Membrane potential at rest
Voltage when two neurons fire
The point where electrical and concentration gradients balance for an ion
Difference between sodium and potassium flux
The Nernst equation calculates the equilibrium potential of an ion. What is the equilibrium potential (E_K⁺) if [K⁺]_in = 100 mM and [K⁺]_out = 5 mM at body temperature?
+61 mV
-61 mV
-80 mV
0 mV
The main function of astrocytes in the CNS includes:
Forming myelin
Scavenging debris
Buffering potassium and supporting neurons metabolically
Conducting action potentials
Which component of a neuron is critical for initiating the action potential?
Soma
Axon
Axon hillock
Dendrites
Using the simplified Nernst equation (E = 61 × log([ion]_out / [ion]_in)), what is the E_Na⁺ if [Na⁺]_out = 145 mM and [Na⁺]_in = 15 mM?
+61 mV
-61 mV
-80 mV
0 mV
Which of the following channels opens during the rising phase of an action potential?
Voltage-gated K+ channels
Ligand-gated Na+ channels
Voltage-gated Na+ channels
The refractory period ensures:
Backward propagation of action potentials
Continuous depolarization
One-way transmission of action potentials
Sustained calcium influx
At rest, the neuronal membrane is most permeable to which ion?
Sodium
Calcium
Chloride
Potassium
The function of the sodium-potassium pump is to:
Equalize Na+ and K+ gradients
Move Na+ out and K+ into the cell against their gradients
Propagate action potentials
Block ion channels
Electrical synapses allow ions to pass through specialized proteins called:
Synapsins
Connexins
Dynamins
Calmodulins
In the central nervous system, which glial cells myelinate axons?
Schwann cells
Astrocytes
Oligodendrocytes
Microglia
Which neurotransmitter is removed from the synaptic cleft via enzymatic degradation?
GABA
Glutamate
Acetylcholine
Dopamine
Which neurotransmitter system is primarily excitatory in the brain?
Dopaminergic
GABAergic
Glutamatergic
Cholinergic
G-protein coupled receptors (GPCRs) activate which kind of intracellular molecules?
Ion channels
Enzymes only
Second messengers
Neurotransmitters
The endocannabinoids are unique neurotransmitters because they:
Are stored in vesicles
Bind to ionotropic receptors
Are synthesized on demand
Only exist in the spinal cord
The amplitude of graded potentials depends on:
The intensity of the stimulus
The number of action potentials
Sodium channel inactivation
Myelin thickness
Which receptor type is both ionotropic and involved in fast synaptic transmission?
Muscarinic
GABAB
Nicotinic
Dopamine D2
Temporal summation requires:
One input occurring quickly in succession
Multiple neurons firing simultaneously
Action potentials at the soma
Vesicle depletion
Which molecule is responsible for vesicle fusion in neurotransmitter release?
Calcium
SNARE proteins
ATP
Acetylcholine
The Goldman equation accounts for:
Concentration gradients of a single ion
Passive diffusion only
Multiple ion permeabilities
Graded potentials
During the falling phase of an action potential, which channel is primarily open?
Sodium
Calcium
Potassium
Chloride
Which retinal cells are responsible for detecting low light conditions?
Rods
Cones
Ganglion cells
Bipolar cells
The fovea is specialized for:
Color blindness
High acuity vision
Peripheral vision
Low light detection
The auditory ossicles function to:
Detect sound waves
Convert vibrations into fluid waves
Amplify sound to the cochlea
Activate hair cells directly
Which fluid in the cochlea contains a high concentration of potassium?
Perilymph
Endolymph
Cerebrospinal fluid
Plasma
Which receptor detects fine touch and vibration near the skin surface?
Ruffini’s ending
Pacinian corpuscle
Meissner’s corpuscle
Merkel’s disk
Which structure controls reflexive eye movement in response to visual stimuli?
Hypothalamus
Superior colliculus
LGN
Retina
Which taste modality is detected by direct Na+ influx?
Bitter
Sweet
Umami
Salty
TRPV1 receptors are involved in detecting:
Cold
Sweet taste
Heat and capsaicin
Proprioception
The dorsal column-medial lemniscal pathway transmits:
Pain and temperature
Light and sound
Touch and proprioception
Vision and balance
Which structure is key in forming long-term declarative memories?
Amygdala
Cerebellum
Hippocampus
Prefrontal cortex
The cerebellum is essential for:
Hormone regulation
Memory consolidation
Coordinated movement
Olfactory processing
Which motor neurons innervate extrafusal muscle fibers?
Beta
Gamma
Alpha
Delta
Which descending tract is primarily responsible for voluntary motor control?
Rubrospinal tract
Vestibulospinal tract
Corticospinal tract
Tectospinal tract
A patient with Brown-Séquard syndrome would most likely experience:
Loss of touch on one side and pain on the opposite
Bilateral blindness
Global amnesia
Loss of hearing in both ears
What sensory coding strategy helps distinguish odor identity?
Temporal coding
Frequency coding
Population coding
Spatial coding
Which protein binds calcium to trigger muscle contraction?
Actin
Myosin
Troponin
Tropomyosin
The ventral stream of visual processing is associated with:
Where an object is
Motion tracking
Object recognition
Balance
Which motor unit type is most fatigue resistant?
Fast fatigable
Intermediate
Slow
Hybrid
Which cranial nerve is responsible for eye movement and pupillary reflex?
CN II
CN III
CN V
CN VII
Damage to the dorsal root ganglion would most likely impair:
Motor output
Endocrine control
Sensory input
Language processing
Which structure is primarily involved in maintaining balance and posture?
Basal ganglia
Cerebellum
Thalamus
Hippocampus
What is the role of the inferior colliculus in the auditory pathway?
Sound localization
Tonotopy encoding
Cochlear amplification
Vestibular integration
The visual pathway includes which relay station in the thalamus?
MGN
LGN
VPL
VPM
Which neurotransmitter is deficient in Parkinson’s disease?
GABA
Serotonin
Dopamine
Glutamate
Which technique allows real-time observation of calcium dynamics in neurons?
EEG
fMRI
GCaMP imaging
PET scan
What part of the brain is activated during fear conditioning?
Amygdala
Thalamus
Hippocampus
Cerebellum
Which cranial nerve carries auditory information to the brain?
Vestibulocochlear nerve (Cranial Nerve VIII)
Olfactory nerve (Cranial Nerve I)
Optic nerve (Cranial Nerve II)
Trigeminal nerve (Cranial Nerve V)
Which cells in the retina first generate action potentials?
Photoreceptors
Bipolar cells
Horizontal cells
Ganglion cells
The function of central pattern generators (CPGs) is to:
Control voluntary movements
Generate rhythmic motor patterns
Encode pain signals
Process visual input
Which tract decussates at the medullary pyramids?
Dorsal column
Spinothalamic
Corticospinal
Rubrospinal
Which glial cell responds to injury and acts as the brain’s immune defense?
Schwann cell
Oligodendrocyte
Microglia
Astrocyte
A lesion to the left optic tract would cause:
Blindness in the left eye
Right visual field loss
Tunnel vision
Central scotoma
Which ion is most responsible for depolarization during synaptic transmission?
K+
Ca2+
Cl-
Na+
Which protein initiates vesicle docking during neurotransmitter release?
Connexin
Troponin
SNARE
Ankyrin
Which visual stream is responsible for processing motion and spatial location?
Lateral stream
Ventral stream
Dorsal stream
Anterior stream
The somatotopic map in the primary somatosensory cortex is called:
Cortical ring
Retinotopy
Motor arc
Homunculus
Which neuromodulator is primarily linked to reward and reinforcement?
Acetylcholine
Norepinephrine
Which of the following describes saltatory conduction?
Ion flow through dendrites
AP propagation in unmyelinated axons
AP jumping between nodes of Ranvier
Continuous propagation of synaptic potential
In synaptic facilitation, a second EPSP is stronger due to:
Ion channel desensitization
Depleted vesicle pool
Residual calcium
Lower membrane resistance
Which type of receptor is both G-protein coupled and inhibitory?
AMPA
GABA-A
GABA-B
NMDA
What is the typical resting membrane potential of a mammalian neuron?
+30 mV
0 mV
-65 mV
-120 mV
Which of the following statements is TRUE about the Na⁺/K⁺ ATPase pump?
It transports 3 K⁺ in and 2 Na⁺ out
It uses ATP to restore equilibrium after action potentials
It transports 3 Na⁺ out and 2 K⁺ in
It moves ions down their concentration gradients
