Neurobiology Ch 15 Dashboard Q's

Which structure is not part of the pathway by which olfactory signals first reach cortex?
a. Olfactory epithelium
b. Olfactory bulb
c. Olfactory thalamus
d. Olfactory nerve
e. Olfactory tract

C

In terms of scent detection and tracking capabilities in humans,
a. the olfactory epithelium of humans is larger than that of most canines.
b. percentage-wise, humans devote more of their cortex to olfaction than do rats.
c. humans (like dogs) can follow scent trails by frequent sniffing with orthogonal digressions.
d. humans can detect most chemical compounds at levels of less than one part per billion.
e. human olfactory capabilities exceed those of almost all other mammals.

C

Which statement about human odorant perception is false?
a. The compound ethyl mercaptan is added to natural gas because this odorant is universally detectable by healthy humans.
b. While some anosmias may ensue from olfactory receptor gene deficits, this has been difficult to substantiate.
c. Olfactory hallucinations can be an early indicator of schizophrenia.
d. Our ability to identify odors declines substantially with age.
e. A "scratch and sniff" test is used by clinicians to aid early diagnosis of neurodegenerative disorders.

A

Which is not an established odorant-mediated response or capability of humans?
a. Pheromone-based sexual attraction mediated by the vomeronasal organ
b. Increased gastric motility in response to appetizing odors
c. Infant recognition of, and increased suckling in response to, their mother's odor
d. A mother's ability to recognize her own baby based upon odor
e. Gagging or vomiting in response to a particularly noxious odor

A

Olfactory receptors are found at the highest concentration in
a. the olfactory ensheathing cells.
b. the olfactory cell cilia.
c. the cribriform plate.
d. Bowman's gland cells.
e. olfactory stem cells.

B

Olfactory receptors most closely resemble which protein in structure and mechanism of action?
a. Tastant receptor for salt
b. Voltage-gated ion channels
c. Ion pumps
d. Muscarinic acetylcholine receptor
e. Ionotropic neurotransmitter receptors

D

Odorant receptor genes and/or proteins
a. constitute a unique gene family with no structural similarities to other receptor families.
b. vary greatly in structure between vertebrate and invertebrate animals (e.g., in terms of number of transmembrane regions and their ability to interact with G-proteins).
c. possess introns only in humans, allowing for greater alternative splicing and increased diversity.
d. constitute approximately 3-5% of the genome of mammals.
e. are expressed in overlapping patterns in olfactory receptor neurons resulting in each neuron expressing between 7 and 10 different olfactory receptors.

D

Listed below are the various components of the olfactory transduction process:
1. Golf G-protein
2. Voltage-gated sodium channel
3. Calcium-activated chloride channel
4. cAMP-gated ion channel
5. Adenylyl cyclase III
Which of the following is the correct order in which these components are activated?
a. 5; 1; 4; 3; 2
b. 1; 5; 4; 3; 2
c. 1; 5; 4; 2; 3
d. 5; 4; 1; 3; 2
e. 2; 1; 5; 4; 3

B

A mouse model with anosmia has been generated using gene knockout techniques. Removing which gene would lead to anosmia?
a. Gs subunit
b. Adenyl cyclase III
c. Diacylglycerol (DAG)
d. TRP channel (specifically M5)
e. H+-sensitive TRP channel

B

In humans, the olfaction-responsive brain area that responds to multimodal stimuli (such as the sight and smell of food) is located in
a. pyriform cortex.
b. orbitofrontal cortex.
c. the hippocampus.
d. the amygdala.
e. the olfactory tubercle.

B

Stephanie has damage to her insular cortex. Which sense would have difficulty processing?
a. Olfaction
b. Vision
c. Somatosensory
d. Pain
e. Taste

E

Samuel is having difficulty distinguishing bitter tastes. In which location might he have damage?
a. Cranial nerve IX
b. Cranial nerve I
c. Cranial nerve VII
d. Cranial nerve X
e. Nucleus of the solitary tract

A

Sour substances activate taste cells by
a. first binding to other organic compounds found in saliva.
b. binding to G-protein-coupled receptors.
c. changing the potassium equilibrium potential of taste cells.
d. the depolarizing effect of protons entering taste cells.
e. All of the above

D

The sweet transduction system involves
a. heterodimeric G-protein-coupled receptors.
b. activation of G-proteins.
c. activation of phospholipase C.
d. IP3 activation of TRPM5 channels.
e. All of the above

E

Which mechanism for the neural encoding of taste perception has the strongest experimental support?
a. Lateral inhibition
b. Second messenger discrimination
c. Labeled lines
d. Functional reactivation
e. Sparse coding

C