In olfactory neurons, it is estimated that activation of the olfactory receptors results in an increase of roughly 200,000 molecules of cAMP per second. 1a) If an activated receptor produces one molecule of cAMP every 30 seconds, how many molecules of this receptor must be working in an activated neuron? How many G-alpha subunits are required in an activated neuron? 1b) If one receptor molecule is capable of activating 500 G-proteins, how many receptors will be activated?

In olfactory neurons, it is estimated that activation of the olfactory receptors results in an increase of roughly 200,000 molecules of cAMP per second. 1a) If an activated receptor produces one molecule of cAMP every 30 seconds, how many molecules of this receptor must be working in an activated neuron? How many G-alpha subunits are required in an activated neuron? 1b) If one receptor molecule is capable of activating 500 G-proteins, how many receptors will be activated?

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter4: Principles Of Neural And Hormonal Communication

Section: Chapter Questions

Problem 15RE

See similar textbooks

Similar questions

1)The concept of saturation is defined as? a) The ability of a receptor to bind only one type or a limited number of structurally related types of chemical messengers. b) The degree to which receptors are occupied by messengers. c) A decrease in the total number of target-cell receptors for a given messenger d) The increased responsiveness of a target cell to a given messenger 2. Phosphodiesterase activity produces one of the following actions a) Breakdown cAMP b) Increases cAMP c) Increases PKC activity d) Increases cytosolic IP3 levels 3. Phospholipase C leads to one of the following? a) Increase in cAMP b) Breakdown of cAMP c) Increase in cytosolic levels of IP3 and DAG d) A decrease in cytosolic Ca++ concentration
Endothelins are 21-amino acid vasoconstricting peptides produced primarily in the endothelium. They have an important role in vascular homeostasis. Endothelin activates G protein-coupled receptors (GPCRs) ETA or ETB on a target cell. Which subunit of heterotrimeric G protein is released when the receptor is activated? a.) gamme b.) beta c.) alpha
Which receptor undergoes clustering and autophosphorylation in response to activation by a signal? Group of answer choices: a)Ligand-gated ion channels b)Receptor Tyrosine Kinases (RTKs) c)G-Protein Coupled Receptors (GPCRs) d)Nuclear Receptors
1. Ionotropic GABA receptors are ligand-gated Cl channels which open during GABA-ergic signaling. a) Describe how under normal circumstances the opening of these channels leads to an IPSP. Do this in the context of Eci. b) Some cells in the body express a Na*/K+/2Cl cotransporter which pumps Cl- into the ICF. Where these pumps are present, the same GABA receptor is actually excitatory. Again, in the context of Ea describe how the same receptor would be excitatory in cells which actively pump Cl- into the ICF. You do not need to repeat information you provided in part (a)
Help me please
Psilocybin is rapidly de-phosphorylated in the body into psilocin, which is anagonist For the 5-HT 2A Serotonin receptor, which binds the neurotransmitter serotonin as its natural ligand, and acts as a ligand-gated ion channel in the central nervous system. HO. Serotonin (a) Part of the sequence of the 5-HT 24 Receptor is NH₂ ...RQKACKVIGIVFFLFVVMWLAFFITNICDES... Identify the trans-membrane region within this sequence. Do you predict this sequence will Be transmembrane a-Helix or ß sheet? Why? (b) What is the distance spanned by this transmembrane region?
In most neurons, membrane depolarization leads to the opening of voltage-dependent ion channels, generation of an action potential, and, ultimately, an influx of Ca2+, which causes release of neurotransmitter at the axon terminus. Devise a cellular strategy by which hyperpolarization in rod cells could produce excitation of the visual pathway and passage of visual signals to the brain. (Hint: The neuronal signaling pathway in higher organisms consists of a series of neurons that relay information to the brain. The signal released by one neuron can be either excitatory or inhibitory to the following, postsynaptic neuron.)
Dopamine, epinephrine (or norepinephrine) and histamine are important neurotransmitter agonists. When these ligands interact with their cellular receptors, how do they mainly elicit their responses? Choose the correct answer(s) and explain why. a) Activate adenylyl cyclase directly, leading to increased intracellular cAMP levels b) Activate phospholipase C c)Induce or inhibit synthesis of ligand specific intracellular proteins d) Open or close ligand gated ion channels e) Regulate intracellular second messengers through G-protein-coupled receptors
Name three features common to the activation of cytokine receptors and receptor tyrosine kinases. Name one difference with respect to the enzyme activity of these receptors.
After establishing the importance of cGMP in the signaling pathway of the photoreceptor cells, the researchers wish to identify the exact target of cGMP. The researchers suspect that cGMP binds to an ion channel, causing the observed change in the membrane potential between the dark and the light conditions but they are not sure which one. The researchers determine the movement of three different ions (sodium, chloride and potassium) as a function of their respective electrochemical gradient across the plasma membrane: ● Sodium tends to enter the cell Chloride tends to enter the cell Potassium tends to leave the cell The researchers therefore propose three simple hypotheses for the effect of cGMP on the membrane potential of the rod photoreceptor cell: ● Hypothesis A: CGMP binds to a sodium-channel, that opens and lets sodium ions diffuse inside the cell. Hypothesis B: cGMP binds to a chloride-channel, that opens and lets loride ions diffuse inside the cell. Hypothesis C: cGMP binds to…
Explain whether the specificity of interaction will be high or low for each given situation. a. The value of KD of the ligand's interaction to the target receptor is very much lower than the value of KD of the ligand's interaction to off-targets. b. The ligand concentration [L] is higher than the KD value of its interaction with the target and the KD value of its interaction to off-targets.
In the cAMP second messenger pathways, Protein kinase A is directly activated by _________. A) Group of answer choices B) cAMP C) Phosphorylation D) a G protein E) a G protein coupled receptor F) an enzyme