BIO CLASS 7

Question 1

How does the auditory cortex in the temporal lobe receive stimulation from the ear?

Answer 1

Hair cells contacting the tectorial membrane open ion channels to trigger release of neurotransmitter

Perception of sound begins with sound waves vibrating the basilar membrane. This causes hair cells (mechanoreceptors) to come in contact with the tectorial membrane, and this contact opens ion channels in the hair cells. The cells depolarize and release neurotransmitter to stimulate the bipolar auditory neurons that run to the auditory cortex in the temporal lobe.

Question 2

How does absolute threshold function as a measure of sensory perception?

Answer 2

As the minimum stimulus needed to activate sensory receptors at least 50% of the time, this measure of perception varies with age and by person.

Question 3

In the condition myopia the inverted image formed by the lens falls:

Answer 3

in front of the retina

In myopia, the image is formed in front of the retina, generally due to the shape of the eye being too long.

Question 4

Nerve cells that control thermoregulation are concentrated in which portion of the brain?

Answer 4

Hypothalamus

Question 5

The cell bodies of a somatic sensory nerve are located in the:

Answer 5

dorsal root ganglion.