Biology Test Neuroscience Fundamentals 3

Question 1

Which neurotransmitter system is most directly implicated in Parkinson's disease due to degeneration of the substantia nigra?

Accepted Answer

Dopamine

Answer

Parkinson's disease results from the loss of dopaminergic neurons in the substantia nigra pars compacta, reducing dopamine signaling in the striatum.

Question 2

What term describes the period after an action potential during which a neuron cannot fire again regardless of stimulus strength?

Accepted Answer

Absolute refractory period

Answer

During the absolute refractory period, all voltage-gated sodium channels are inactivated, making re-stimulation impossible no matter how large the stimulus.

Question 3

Which glial cell type is responsible for myelinating axons in the central nervous system?

Accepted Answer

Oligodendrocytes

Answer

Oligodendrocytes wrap their membrane extensions around multiple CNS axons, forming myelin sheaths that insulate and speed up signal conduction.

Question 4

The hippocampus is critically involved in which type of memory?

Accepted Answer

Declarative episodic memory

Answer

The hippocampus is essential for forming new declarative (explicit) memories, including episodic memories of personal experiences and semantic facts.

Question 5

Spatial summation in neurons refers to:

Accepted Answer

Simultaneous inputs from multiple synapses combining to reach threshold

Answer

Spatial summation occurs when excitatory postsynaptic potentials from several synapses arrive simultaneously and add together to depolarize the neuron to threshold.

Biology Practice Test

Biology Practice Test

Biology Test Neuroscience Fundamentals 3