Concept explainers
SYNTHESIZE YOUR KNOWLEDGE
There are five basic tastes—sour, salty, sweet, bitter, and "umami." Salt is detected when the concentration of salt outside of a taste bud cell is higher than that inside of it, and ion channels allow the passive leakage of Na+ into the cell. The resulting change in membrane potential (seeConcept 7.4) sends the "salty" signal to the brain. Umami is a savory taste generated by glutamate (glutamicacid, found in monosodium glutamate, or MSG), which is used as a flavor enhancer in foods such as taco-flavored tortilla chips. The glutamate reeeptor is a GPCR, which, when bound, initiates a signaling pathway that ends with a cellular response, pereeived by you as "taste." If you eat a regulär potato chipand then rinse your mouth, you will no longer taste salt. But if you eat a flavored tortilla chip and then rinse, the taste persists. (Try it!) Proposea possiblc explanation for this difference.
Want to see the full answer?
Check out a sample textbook solutionChapter 11 Solutions
Campbell Biology (10th Edition)
Additional Science Textbook Solutions
Human Physiology: An Integrated Approach (8th Edition)
Microbiology with Diseases by Taxonomy (5th Edition)
Campbell Essential Biology (6th Edition) - standalone book
Seeley's Anatomy & Physiology
Marine Biology (Botany, Zoology, Ecology and Evolution)
- Many diabetic patients are warned by their doctors to test their glucose levels by pricking the sides of their fingers rather than the pads. Pricking the sides avoids stimulating which receptor? Krause end bulbs Meissner’s corpuscles Ruffini ending Nociceptorsarrow_forward1) The olfactory receptor neurons in frogs resemble those of mammals, in that they express olfactory receptors that are coupled to a G protein. When the G protein is activated, it activates an adenylyl cyclase to produce cAMP, which then opens cyclic-AMP gated cation channels in the plasma membrane. The opening of these channels depolarizes the membrane, leading to the production of an action potential. Your friend is interested in why neurons stop responding to an odor after prolonged exposure to it, a process called adaptation. He has conducted experiments examining the depolarization of the olfactory receptor neuron, the binding of odorant to the receptor, the activation of the G protein, the levels of CAMP in the cell, and the phosphorylation of adenylyl cyclase. His results are summarized in Table 1. depolarization of neuron? odorant binding to receptor? activation of the G protein? CAMP levels in the cell? adenylyl cyclase phosphorylation? no odor no no no low no Table 1 brief…arrow_forwardCompare the mechanisms of the receptor molecules for salty and sour taste; the taste-receptor molecules for sweetness, bitterness, and umami; and odor-receptor molecules (Indicate if a given sense uses a GPCR, an ion channel etc and how the downstream signal might be different). Drawing is good for this type of question.arrow_forward
- Caffeine is an inhibitor of the enzyme phosphodiesterase. Predict what caffeine will do to my heart rate -- Support with the correct physiological mechanism And you may ask yourself "Well....how did I get to membrane potentials?" If caffeine were applied to the retina, what would happen. Include the mechanism we covered on how you detect lightarrow_forward1. Protein anions have a charge. However, they do not move across the membrane to produce changes in RMP. Why? 2. At the molecular level, what causes the absolute refractory period? 3. At the molecular level, what is different during the relative refractory period? 4. What would happen if Na+ channels opened and stayed open? 5. How is stimulus intensity coded in APs? 6. What effect does AP frequency have on NT release?arrow_forwardPart A Which of the following statements about pain-relief substances is correct? View Available Hint(s) O Endorphins are synthetic pain-killers. O Met-enkephalin has pain-killing ability because of its structural similarity to morphine. O Many natural pain-killing polypeptides are ideal for medical use. O Receptors of opium derivatives are found in all body cells. Submitarrow_forward
- Explain why some taste receptor cells and all olfactoryreceptor cells use G protein-coupled receptors, yet onlyolfactory receptor cells produce action potentials.arrow_forwardwhy would someone who has a damaged esophagous due to acid feel pain on his heart and back? nociceptors have a lot of myelin so any little injury is going to lead to fast signals and a lot of pain neurons from vesicular organs and the soma synapse on the same interneurons nociceptors from vesicular tissue synapse on non-specific asending pathways, so the pain in one neuron will cause pain in all.arrow_forwardMany odorant molecules are highly hydrophobic and concentrate within the olfactory epithelium. They would give a persistent signal independent of their concentration in the environment if they were not rapidly modified. Propose a mechanism for converting hydrophobic odorants into watersoluble derivatives that can be rapidly eliminated.arrow_forward
- Outline the neurochemical transmission and inhibition of pain. Then using the gate-control theory, devise a plan to minimize pain during your next visit to the dentist.arrow_forwardMiraculin is a chemical that causes your sweet taste receptors to be incorrectly activated by H* ions. In the presence of miraculin, what taste would your brain now perceive if you ate something with a low pH (many H")? Bitter Umami Salty Sweet No taste is perceivedarrow_forwardBased on the same attached figure as above (Figure 10.9 in your textbook), what kind of channel permits K+ to pass through the apical-end membrane in hair cells of the ear? (A) Spiral ganglion Tectorial membrane Scala vestibuli Inner hair cells -45 mV Scala tympani Outer hair cells Scala media Organ of Corti Perilymph Low K+ 0mV Endolymph High K+ +80 mV (B) Stria vascularis Basilar membrane Ca²+ Afferent. nerve Depolarization O Nucleus wwww. 00 -Depolarization. Vesicles -Transmitter To brain C₂24arrow_forward
- Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage LearningBiology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning
- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning