Neuroanatomy
What is the correct structural composition of the CNS?
Central Nervous System = brain + spinal cord
What happens when voltage-gated K⁺ channels stay open too long?
Hyperpolarization occurs (makes membrane more negative than resting potential)
Which neuroglial cell helps form the blood-brain barrier?
Astrocytes
What part of the brain houses the primary motor cortex?
Precentral gyrus of the frontal lobe
How many pairs of spinal nerves are there?
31 pairs
What is the correct order, from largest to smallest, of a nerve structure?
Nerve ⇒ fascicle ⇒ axon ⇒ neurolemma (myelin sheath) ⇒ plasma membrane
Graded potentials occur in the ______ segment of the neuron.
receptive (dendritic/cell body)
What disease causes ascending paralysis and affects the PNS?
Guillain–Barré syndrome
What hormone does the suprachiasmatic nucleus regulate through the pineal gland?
Melatonin
What nerve innervates the diaphragm and what plexus does it come from?
Phrenic C3-C5
The plasma membrane of the axon is called the _______.
Axolemma
What type of transport protein requires energy and is highly abundant in neurons?
Sodium-potassium pump (Na⁺/K⁺ ATPase)
Which glial cell produces CSF and where is it found?
Ependymal cells—found lining the ventricles of the brain and central canal of spinal cord
What structure relays sensory information to the cerebrum?
Thalamus
What is the name of the bundle of nerves at the lower end of the spinal cord?
Cauda Equina
Which space does cerebrospinal fluid flow through?
Subarachnoid space (between arachnoid and pia mater)
What does saltatory conduction involve, and is it faster than continuous conduction?
Action potentials jump between Nodes of Ranvier—yes, it’s faster than continuous conduction.
What is the key difference between oligodendrocytes and neurolemmocytes?
Oligodendrocytes myelinate CNS axons; neurolemmocytes (Schwann cells) myelinate PNS axons.
What part of the brain processes and experiences emotions?
Limbic system (amygdala, hippocampus, cingulate gyrus)
What nerve is the longest in the body and what plexus does it originate from?
What is the resting membrane potential of a neuron?
-70 mV
Which type of neuron contains the nucleus?
Multipolar neuron (in CNS; cell body contains nucleus)
What neurotransmitter is low in Parkinson’s disease and plays a role in cognition?
Dopamine
What is the name of CN6?
Abducens
What does the dorsal root ganglion contain and what information does it transmit?
Sensory/Afferent