What is the presumed reason for 'odor blindness' for a single substance?
Explanation
This question assesses the understanding of the molecular basis for specific anosmia (odor blindness), linking it to the absence of a specific receptor protein.
Other questions
Taste impulses from the anterior two-thirds of the tongue are transmitted into the central nervous system via which sequence of nerves?
Where do all taste fibers from the facial, glossopharyngeal, and vagus nerves first synapse in the central nervous system?
What is the primary conclusion drawn from electrophysiological studies regarding the mechanism of rapid taste adaptation?
An animal given injections of excessive amounts of insulin, leading to depleted blood sugar, would automatically choose which type of food?
What is the total surface area of the olfactory membrane in humans?
What is the primary function of the Bowman glands in the olfactory membrane?
In the mechanism for exciting olfactory cells, what is the role of the G-protein after it is activated by an odorant-receptor complex?
What is the average membrane potential inside an unstimulated olfactory cell?
What is the postulated neuronal mechanism for the rapid and near-complete adaptation of smell sensations that occurs within a minute?
What does the text suggest about the number of primary sensations of smell compared to taste and color vision?
What is the primary characteristic of smell intensity discrimination compared to other sensory systems like vision and hearing?
In the olfactory bulb, what is the approximate number of olfactory cell axons that terminate in a single glomerulus?
The medial olfactory area, part of the primitive olfactory system, feeds primarily into which part of the brain's limbic system?
What is the primary function attributed to the 'less old' lateral olfactory system?
What is a unique feature of the lateral olfactory area's signal pathway to the cerebral cortex?
Taste signals from the base of the tongue and other parts of the pharyngeal region are transmitted into the tractus solitarius primarily by which nerve?
In the central nervous system, where are taste reflexes for controlling saliva secretion primarily integrated?
What is the primary reason given for believing that taste preference is mainly a central nervous system phenomenon rather than a receptor-level one?
What are the olfactory cells, which act as receptors for smell sensation, classified as?
How many olfactory hairs, also known as olfactory cilia, project from the knob of a single olfactory cell?
What is the primary purpose of the cascading effect in the olfactory signal transduction pathway, starting from a single odorant molecule?
Besides being volatile, what two physical properties are helpful for a substance to be smelled?
During stimulation by most odorants, the number of action potentials in olfactory nerve fibers increases to what rate?
Which substance is mentioned as being detectable at a concentration of one 25 trillionth of a gram per milliliter of air, demonstrating the very low threshold for smell?
What is the relationship between the olfactory bulb, the olfactory tract (cranial nerve I), and the brain?
After entering the brain, the olfactory tract divides into two primary pathways. One passes medially into the medial olfactory area; where does the other pathway pass?
What is the primary function of the 'newer' olfactory pathway that passes through the dorsomedial thalamic nucleus?
What is the function of the centrifugal nerve fibers that pass from the brain back to the olfactory bulb?
What is the approximate location of the gustatory cortex, where taste signals are consciously perceived?
What happens to the taste preferences of an adrenalectomized, salt-depleted animal?
What is taste aversion, as described in the text?
In the olfactory signal transduction pathway, which enzyme is responsible for converting ATP to cAMP?
How much do olfactory receptors typically adapt in the first second or so after stimulation?
The existence of odor blindness for more than 50 different single substances provides further support for what concept?
The olfactory tract and bulb are an anterior outgrowth of brain tissue and lie over which bony structure?
In the olfactory bulb, dendrites from which two types of cells receive synapses from the olfactory cell neurons within the glomeruli?
Removal of the lateral olfactory areas in an animal abolishes the more complicated olfactory conditioned reflexes but hardly affects what?
What is the summary description of the 'primitive olfactory system' (medial olfactory area)?
Which cranial nerve transmits taste sensations from the circumvallate papillae?
How do third-order taste neurons from the thalamus reach the gustatory cortex?
Taste sensations adapt rapidly, often almost completely within how much time of continuous stimulation?
What is the approximate number of olfactory cells in the human olfactory epithelium?
Each odorant receptor protein is a long molecule that threads its way through the membrane of an olfactory cilium about how many times?
What is the effect of most odorants on the membrane potential of the olfactory cell?
The rate of olfactory nerve impulses changes approximately in proportion to what property of the stimulus?
Which part of the brain, originally subserving olfaction, later evolved into the basal brain structures that control emotions and is now called the limbic system?
What is the function of the septal nuclei in the context of the primitive olfactory system?
Which area of the cerebral cortex receives direct sensory signals from the lateral olfactory area without them first passing through the thalamus?
What are the three main olfactory systems summarized in the text?