Exam 5: Lecture 75: AI Questions

Question 1

Which of the following sensory modalities is transduced through labeled line coding?
A. Pain
B. Vision
C. Proprioception
D. All of the above

Answer 1

D

Question 2

The primary distinction between fast and slow-adapting receptors is:
A. The location of the receptor in the body.
B. The myelination of the axons they are attached to.
C. The ability to sustain or reduce signaling with continuous stimulation.
D. Their reliance on neurotransmitter vesicle release.

Answer 2

C

Question 3

What adaptation mechanism contributes to non-adaptive receptors such as nociceptors?
A. Increased Na+ channel inactivation
B. Constant generator potential
C. Reduced receptor sensitivity
D. Progressive desensitization to neurotransmitters

Answer 3

B

Question 4

Which tract primarily carries somatic proprioceptive information to the brain?
A. Dorsal Column-Medial Lemniscal (DCML) system
B. Anterolateral system
C. Spinothalamic tract
D. Rubrospinal tract

Answer 4

A

Question 5

Decussation in the DCML pathway occurs at which point?
A. Spinal cord
B. Medulla
C. Thalamus
D. Midbrain

Answer 5

B

Question 6

What is the adequate stimulus for thermoreceptors?
A. Electrical gradients
B. Pressure changes
C. Temperature changes
D. Chemical gradients

Answer 6

C

Question 7

Receptive fields that overlap help to:
A. Increase stimulus intensity.
B. Improve spatial localization of stimuli.
C. Reduce redundancy in sensory input.
D. Adapt to tonic stimuli.

Answer 7

B

Question 8

What type of ion channels do nociceptors primarily use to transduce pain signals?
A. Voltage-gated calcium channels
B. Transient receptor potential (TRP) channels
C. Nicotinic acetylcholine receptors
D. G-protein coupled receptors

Answer 8

B

Question 9

Which ascending tract is most associated with transmitting crude touch and pressure sensations?
A. Anterolateral system
B. DCML system
C. Corticospinal tract
D. Vestibulospinal tract

Answer 9

A

Question 10

In the somatotopic map of the cerebral cortex, which region occupies the largest area?
A. Legs
B. Torso
C. Hands
D. Internal organs

Answer 10

C

Question 11

The role of the thalamus in sensory signal processing is to:
A. Filter, amplify, and relay sensory information to the cerebral cortex.
B. Initiate motor reflexes in response to sensory input.
C. Integrate sensory and motor pathways.
D. Generate direct motor commands.

Answer 11

A

Question 12

Damage to the dorsal column of the spinal cord will result in:
A. Loss of pain and temperature sensation ipsilaterally.
B. Loss of fine touch and proprioception ipsilaterally.
C. Loss of motor function contralaterally.
D. Complete paralysis bilaterally.

Answer 12

B

Question 13

A lesion in the medial lemniscus of the brainstem would impair:
A. Crude touch and pain sensation.
B. Fine touch and vibration sensation.
C. Auditory processing.
D. Motor coordination.

Answer 13

B

Question 14

Saltatory conduction primarily benefits the nervous system by:
A. Increasing signal accuracy.
B. Enhancing neurotransmitter release.
C. Allowing faster conduction velocities.
D. Strengthening axonal durability.

Answer 14

C

Question 15

Which neurotransmitter is involved in fast excitatory synapses within the somatosensory system?
A. Dopamine
B. Glutamate
C. GABA
D. Acetylcholine

Answer 15

B

Question 16

most likely located in the:
A. Cerebellum
B. Contralateral cerebral cortex
C. Ipsilateral spinal cord (dorsal column)
D. Contralateral thalamus

Answer 16

C

Question 17

In a veterinary clinical case, loss of nociception in the pelvic limbs could indicate damage to the:
A. Anterolateral tract in the lumbar spinal cord.
B. Dorsal root ganglion of the thoracic spine.
C. Medial lemniscus in the medulla.
D. Lateral corticospinal tract in the cervical region.

Answer 17

A

Question 18

Which sensory receptor type would be most affected by a mutation that disrupts voltage-gated sodium channel function?
A. Mechanoreceptors
B. Photoreceptors
C. Thermoreceptors
D. Nociceptors

Answer 18

D

Question 19

The primary function of the corticospinal tract is to:
A. Relay sensory feedback to the thalamus.
B. Control voluntary, fine motor movements.
C. Maintain postural reflexes.
D. Mediate autonomic functions.

Answer 19

B

Question 20

A veterinary patient displays hyperreflexia and spastic paralysis in the hind limbs. This suggests damage to:
A. Lower motor neurons in the lumbar region.
B. Upper motor neurons in the thoracic region.
C. The dorsal root ganglia.
D. The cerebellar peduncles.

Answer 20

B

Question 21

The rubrospinal tract contributes primarily to:
A. Fine motor control of distal limbs.
B. Postural adjustments of the trunk.
C. Reflexive movements of the head.
D. Auditory signal modulation.

Answer 21

A

Question 22

Which sensory pathway decussates in the spinal cord rather than the medulla?
A. DCML system
B. Anterolateral system
C. Spinocerebellar tract
D. Corticospinal tract

Answer 22

B

Question 23

A horse with a lesion in the DCML pathway would likely exhibit:
A. Impaired nociception.
B. Loss of crude touch sensation.
C. Impaired fine touch and proprioception.
D. Hyperalgesia.

Answer 23

C

Question 24

Proprioceptive information from the hind limb reaches the cerebellum via the:
A. Ventral spinocerebellar tract.
B. Dorsal spinocerebellar tract.
C. Anterolateral system.
D. Medial longitudinal fasciculus.

Answer 24

B

Question 25

The progressive inactivation of sodium channels during receptor adaptation is characteristic of:
A. Chemoreceptors.
B. Mechanoreceptors.
C. Thermoreceptors.
D. Tonic receptors.

Answer 25

B

Question 26

Rapidly adapting receptors are most useful for:
A. Sensing prolonged stimuli.
B. Detecting the onset and offset of stimuli.
C. Regulating autonomic homeostasis.
D. Providing tonic sensory input to the CNS.

Answer 26

B

Question 27

A dog suffers from sudden blindness but retains a normal pupillary light reflex. The lesion is likely in the:
A. Retina
B. Optic nerve
C. Optic radiations or visual cortex
D. Oculomotor nerve

Answer 27

C

Question 28

In an animal presenting with anisocoria (unequal pupils), which structure is most likely affected?
A. Optic chiasm
B. Oculomotor nerve
C. Trigeminal nerve
D. Cerebellum

Answer 28

B

Question 29

Damage to the vestibulocochlear nerve would primarily impair:
A. Motor coordination.
B. Auditory and balance functions.
C. Visual tracking.
D. Olfactory processing.

Answer 29

B

Question 30

Sharks use electroreception to detect prey. The structure responsible for this is the:
A. Ampullae of Lorenzini.
B. Lateral line system.
C. Otolith organs.
D. Baroreceptors.

Answer 30

A

Question 31

What adaptation gives certain animals the ability to detect infrared radiation?
A. TRPV1 ion channels
B. Phototransduction pathways
C. Specialized olfactory receptors
D. Piezo1 mechanosensors

Answer 31

A

Question 32

The “labeled line” theory in sensory systems explains:
A. The specificity of nerve fibers for a particular sensory modality.
B. The convergence of multiple sensory inputs.
C. Cross-talk between adjacent sensory pathways.
D. Redundancy in sensory coding.

Answer 32

A

Question 33

Why do lesions in the brainstem often produce mixed sensory and motor deficits?
A. The brainstem integrates sensory and motor pathways.
B. The brainstem is primarily responsible for autonomic control.
C. The brainstem contains commissural fibers for bilateral coordination.
D. The brainstem lacks functional specialization.

Answer 33

A

Question 34

A dog exhibits loss of contralateral pain sensation and ipsilateral proprioceptive deficits. The most likely site of the lesion is:
A. The midbrain.
B. The spinal cord.
C. The thalamus.
D. The cerebellum.

Answer 34

B

Question 35

The primary function of the nodes of Ranvier is to:
A. Slow conduction to synchronize sensory signals.
B. Enhance saltatory conduction for efficient signal transmission.
C. Regulate neurotransmitter release.
D. Prevent backpropagation of action potentials.

Answer 35

B