Question 1

Which of the following best describes the process of lateral inhibition as illustrated in the first image, and what is its primary function in sensory pathways?

Accepted Answer

Lateral inhibition involves the most strongly stimulated neuron (B) inhibiting its neighbors (A and C), thereby sharpening the localization of the stimulus and increasing sensory acuity.

Question 2

In the olfactory epithelium (second image), which cell type is responsible for the direct detection of odorant molecules, and what is the sequence of events following odorant binding?

Accepted Answer

Olfactory receptor cells; odorant binds to receptors, leading to graded potentials and then action potentials transmitted via CN I to the olfactory cortex.

Question 3

The third image shows a taste bud. Which structure within the taste bud is responsible for detecting dissolved chemicals, and what is the immediate result of this detection?

Accepted Answer

Gustatory receptor cells; their microvilli bind chemicals, leading to the opening of ion channels and generation of a receptor potential.

Question 4

Refer to the fourth image. Which cranial nerves are primarily responsible for transmitting taste information from the tongue to the brain, and what is the correct sequence of the gustatory pathway?

Accepted Answer

CN VII, CN IX, CN X; tongue → medulla oblongata → thalamus → gustatory cortex

Question 5

Which of the following best explains why a larger receptive field results in lower sensory acuity?

Accepted Answer

Larger receptive fields have higher convergence, causing multiple stimuli to be perceived as one, thus reducing the ability to localize stimuli precisely.

Question 6

A patient presents with difficulty seeing near objects clearly, but can see distant objects without issue. Which condition does this describe, and what is the physiological basis?

Accepted Answer

Hyperopia; the eyeball is too short or the lens is too weak, causing light to focus behind the retina.

Question 7

Which of the following best describes the role of cGMP in phototransduction within rods?

Accepted Answer

cGMP keeps Na$$^+$$ channels open in the dark, maintaining the depolarized state of the photoreceptor cell.

Question 8

Which of the following statements about tonic and phasic receptors is correct?

Accepted Answer

Tonic receptors maintain a sustained response to a constant stimulus, while phasic receptors respond with a burst of activity and then adapt.

Question 9

Which of the following best explains the coding of stimulus intensity in sensory neurons?

Accepted Answer

Stimulus intensity is coded by the frequency of action potentials and the amount of neurotransmitter released.

Question 10

Which of the following is true regarding the neural pathway for pain perception?

Accepted Answer

Pain signals travel from nociceptors to the spinal cord, ascend via the spinothalamic tract to the thalamus, and then to the somatosensory cortex.

Question 11

Which of the following best describes the function of the organ of Corti in the cochlea?

Accepted Answer

It contains hair cells that transduce mechanical vibrations into electrical signals for hearing.

Question 12

Which of the following statements about the maculae in the vestibular system is correct?

Accepted Answer

The maculae in the utricle detect horizontal acceleration, while those in the saccule detect vertical acceleration.

Question 13

Which of the following best describes the effect of endogenous opioids on pain perception?

Accepted Answer

They inhibit the release of neurotransmitters from nociceptors, reducing the transmission of pain signals to the brain.

Question 14

Which of the following is a correct statement about the labeled lines principle in sensory coding?

Accepted Answer

Each labeled line is a specific neural pathway that carries information about a particular type of stimulus to a specific region of the brain.

Question 15

Which of the following best explains why rods are more sensitive to low light than cones?

Accepted Answer

Rods have greater convergence onto bipolar cells, allowing them to summate signals from a larger area.

Question 16

Which of the following best describes the process of adaptation in sensory receptors?

Accepted Answer

Adaptation is the process by which a receptor's response to a constant stimulus decreases over time.

Study Guide for Sensory System: Anatomy & Physiology I (BIOL 2401)

Study Guide - Practice Questions

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