Chapter 7 (part 3) Sensory Physiology

Question 1

based on the physics of sound and the physiology of the ear, the nerves, and the brain regions involved in processing acoustic info

Answer 1

Hearing

Question 2

energy that is transmitted through vibration of the medium’s molecules

Answer 2

Sound energy

Question 3

When there are no molecules, as in a vacuum, there can be no sound

Answer 3

true

Question 4

Sound Transmission in the Ear

Answer 4

tymapnic membrane deflects

middle ear bone moves

membrane in oval window moves

basilar membrane movment

membrane in round window moves

Question 5

Vestibular information is used to:

Answer 5

• To control eye movement
• To maintain posture and balance
• To provide awareness of body position and acceleration

Question 5

Neural Pathways in Hearing

Answer 5

• Cochlear nerve fibers synapse with interneurons in the brainstem.
• From the brainstem a multineuron pathway transmits information through the thalamus to the auditory cortex in the temporal lobe.

Question 6

Vestibular information is integrated with information from __________

Answer 6

proprioceptors

Question 6

fibers used to transmit information through the brainstem and thalamus to the vestibular centers in the parietal lobe.

Answer 6

Vestibular nerve fibers

Question 7

Chemicals binding to specific chemoreceptors are responsible for the detection of taste and smell.

Answer 7

Chemical Senses

Question 8

other term for taste

Answer 8

gustation

Question 9

groups of cells arranged around a hollow pore
on the tongue

Answer 9

Taste buds

Question 10

increase the surface area, and contain membrane proteins that transduce a chemical into a receptor potential on tongue

Answer 10

Microvilli

Question 11

divide and differentiate to continually replace taste receptor cells damaged in the harsh environment

Answer 11

Basal cells (of taste buds)

Question 12

To enter the pores of the taste buds, food molecules must be dissolved in liquid

Answer 12

true

Question 13

Types of Taste Receptors
Salt taste

Answer 13

sodium ions

Question 14

Types of Taste Receptors
Sour taste

Answer 14

hydrogen ions

Question 15

Types of Taste Receptors
Sweet taste

Answer 15

glucose

Question 16

Types of Taste Receptors
associated with poisonous substances, especially plant alkaloids

Answer 16

Bitter flavor

Question 17

Types of Taste Receptors
depolarize via a G protein-coupled receptor mechanism

associated with the taste of glutamate and is sometimes described as savory or flavorful

Answer 17

Umami receptor

Question 18

• lie in the olfactory epithelium in the upper part of the nasal cavity
• last for only about two months, so they are constantly replaced by new cells produced from stem cells in the olfactory epithelium

Answer 18

Olfactory Receptors

Question 19

Olfactory Receptors have ___________, contain the receptor proteins that provide the binding sites for odor molecules.

Answer 19

cilia

Question 20

Axons of the neurons form the olfactory nerve which is what number cranial nerve

Answer 20

(cranial nerve l)

Question 21

• Proteins in the mucus interact with the odorant molecules, transport them to the receptors, and facilitate their binding to the receptors.

Answer 21

Smell

Question 22

in smell, Stimulated odorant receptors activate a
_______________ that increases cAMP, which in turn opens nonselective cation channels and depolarizes the cell.

Answer 22

G protein-mediated pathway

Question 23

Some are born with genetic defects resulting in lack of the ability to smell

Answer 23

(anosmia)

Question 24

Factors that Affect the Sense of Smell

Answer 24

* Attentiveness * Hunger (greater in hungry subjects) * Gender (women have keener olfactory sensitivities) * Smoking (decreased sensitivity) * Age (decreases with age) * State of the olfactory mucosa (decreases when the mucosa is congested, as in a head cold)

Question 25

What changes take place in neurotransmitter release from the rods or cones when they are exposed to light?

Answer 25

When exposed to light, rods and cones in the retina decrease their neurotransmitter release due to a process called hyperpolarization, meaning they become more negatively charged, which in turn reduces the amount of glutamate released at the synapse; essentially, the more light, the less neurotransmitter is released.

Question 26

What is the relationship between head movement and cupula movement in a semicircular canal?

Answer 26

When the head moves, the fluid (endolymph) inside the semicircular canal lags behind due to inertia, causing the cupula to bend in the opposite direction of the head movement,

Question 27

In what ways are the sensory systems for taste and olfaction similar? In what ways are they different?

Answer 27

Both odors and tastes involve molecules that stimulate specific chemoreceptors. Although humans commonly distinguish taste as one sense and smell as another, they work together to create the perception of flavor. A person's perception of flavor is reduced if he or she has congested nasal passages. However, they differ in their mechanisms and the range of sensory information they provide. When we chew food or sip wine, chemicals are vaporized into air passages that connect the mouth and the back of the nose, stimulating olfactory receptors and allowing us to realize the subtleties of flavor. Other aspects of the taste experience, such as food texture and temperature, engage additional senses.