Intracellular Signaling and Cell Membrane
60 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which class of enzyme-coupled receptors is the most common?

  • Receptor tyrosine kinases (correct)
  • Phospholipase C
  • Ras
  • Gq
  • What activity does the receptor tyrosine kinase have?

  • GTP binding
  • Activation of Ras
  • Intrinsic enzyme activity (correct)
  • Phosphorylation
  • What happens when the receptor tyrosine kinase binds to a ligand?

  • It phosphorylates itself on specific residues
  • It dimerizes and activates a tyrosine kinase (correct)
  • It activates phospholipase C
  • It binds to GTP and activates Ras
  • What is the function of Ras in the signaling cascade?

    <p>It binds to GTP and activates Raf</p> Signup and view all the answers

    Which of the following is NOT a ligand example for receptor tyrosine kinases?

    <p>Phospholipase C</p> Signup and view all the answers

    What is the role of the ligand in the signaling process of receptor tyrosine kinases?

    <p>It activates the receptor</p> Signup and view all the answers

    What is the function of phospholipase C in the signaling pathway of receptor tyrosine kinases?

    <p>It cleaves phosphatidylinositol 4,5-bisphosphate</p> Signup and view all the answers

    What does the activation of Ras lead to in the signaling pathway of receptor tyrosine kinases?

    <p>Activation of Raf</p> Signup and view all the answers

    What is the function of Raf in the signaling cascade of receptor tyrosine kinases?

    <p>It activates MEK</p> Signup and view all the answers

    What is the role of the ligand in the dimerization of receptor tyrosine kinases?

    <p>It brings two receptor monomers together</p> Signup and view all the answers

    Which pathway is most commonly associated with RTK activation?

    <p>Ras-Raf-MAP kinase pathway</p> Signup and view all the answers

    What is the key signaling mechanism that is key to insulin signaling?

    <p>PI-3-Kinase (PI3K) → Akt system</p> Signup and view all the answers

    Which molecule is the second messenger in the PI-3-Kinase (PI3K) → Akt system?

    <p>PIP3</p> Signup and view all the answers

    What is the effector molecule in the PI-3-Kinase (PI3K) → Akt system?

    <p>Akt</p> Signup and view all the answers

    What is the key mediator that relaxes smooth muscle in a wide variety of blood vessels and visceral organs?

    <p>Nitric oxide (NO)</p> Signup and view all the answers

    What is the molecule produced enzymatically by the action of nitric oxide synthase (NOs) on L-arginine?

    <p>Nitric oxide (NO)</p> Signup and view all the answers

    What molecule is produced from GTP by guanylyl cyclase (GC) in the nitric oxide-mediated signaling pathway?

    <p>cGMP</p> Signup and view all the answers

    What molecule is activated by elevations in cytosolic cGMP in the nitric oxide-mediated signaling pathway?

    <p>protein kinase (usually PKG)</p> Signup and view all the answers

    What is the result of PKG activity in many cases in the nitric oxide-mediated signaling pathway?

    <p>Smooth muscle relaxation</p> Signup and view all the answers

    What is the most common pathway associated with RTK activation?

    <p>Ras-Raf-MAP kinase pathway</p> Signup and view all the answers

    Which of the following is a general model of intracellular signaling?

    <p>Signal amplification</p> Signup and view all the answers

    What is the function of phospholipase C in the signaling pathway of receptor tyrosine kinases?

    <p>Production of second messengers</p> Signup and view all the answers

    What is the role of Ras in the signaling cascade of receptor tyrosine kinases?

    <p>Activation of downstream kinases</p> Signup and view all the answers

    What is the effector molecule in the PI-3-Kinase (PI3K) → Akt system?

    <p>Akt</p> Signup and view all the answers

    What is the function of Raf in the signaling cascade of receptor tyrosine kinases?

    <p>Activation of MEK</p> Signup and view all the answers

    What is the key mediator that relaxes smooth muscle in a wide variety of blood vessels and visceral organs?

    <p>Nitric oxide</p> Signup and view all the answers

    Which of the following is a key function of membrane receptors in intracellular signaling?

    <p>Detecting extracellular signals</p> Signup and view all the answers

    What is the role of effectors in intracellular signaling?

    <p>Activation of signaling cascades</p> Signup and view all the answers

    What happens when the concentration of the first messenger (ligand) increases in intracellular signaling?

    <p>Binds to the cell membrane receptor</p> Signup and view all the answers

    What is the typical process of signal termination in intracellular signaling?

    <p>All of the above</p> Signup and view all the answers

    What does the model of intracellular signaling offer?

    <p>A way to categorize signaling events</p> Signup and view all the answers

    Which type of cell membrane receptor is described in the text?

    <p>G-Protein-Coupled Receptors (GPCR)</p> Signup and view all the answers

    Which of the following is true about G-protein-coupled receptors (GPCRs)?

    <p>Almost half of medications act on GPCRs</p> Signup and view all the answers

    What is the structure of a G-protein-coupled receptor (GPCR)?

    <p>GPCRs have 3 protein subunits: α, β, γ</p> Signup and view all the answers

    Which G-protein mechanism uses calcium and IP3 as second messenger systems?

    <p>Gq</p> Signup and view all the answers

    What is the impact of Gs GPCR on adenylyl cyclase activity?

    <p>Gs GPCR stimulates adenylyl cyclase activity</p> Signup and view all the answers

    What is the result of cAMP binding to protein kinase A (PK A)?

    <p>cAMP activates PK A activity</p> Signup and view all the answers

    What is the function of adenylyl cyclase in G-protein-coupled receptor signaling?

    <p>Adenylyl cyclase converts ATP to cAMP</p> Signup and view all the answers

    According to the text, what is the concentration gradient for calcium between the cytosol and the endoplasmic reticulum and extracellular space?

    <p>1 – 3 mmol</p> Signup and view all the answers

    What happens to the cytosolic calcium concentration if a channel that allows calcium to cross the cell membrane is opened?

    <p>It increases</p> Signup and view all the answers

    What is the impact on the membrane potential if sodium enters the cell?

    <p>It becomes more inside-positive</p> Signup and view all the answers

    What is the impact on the activation of certain membrane-associated proteins if the membrane becomes more inside-positive or more inside-negative?

    <p>It impacts the activation of certain membrane-associated proteins</p> Signup and view all the answers

    What is the function of Gq-alpha in the Gq GPCR signaling pathway?

    <p>It activates phospholipase C</p> Signup and view all the answers

    What is the ligand example for receptor tyrosine kinases?

    <p>All of the above</p> Signup and view all the answers

    Which molecule is phosphorylated by the receptor tyrosine kinase in the signaling process?

    <p>Ras</p> Signup and view all the answers

    What is the function of phosphoinositide-3-kinase (PI3K) in the PI-3-Kinase (PI3K) → Akt system?

    <p>Attaches an additional phosphate to PIP2</p> Signup and view all the answers

    What is the key role of Ras in the signaling cascade of receptor tyrosine kinases?

    <p>Activation of Raf</p> Signup and view all the answers

    What is the function of guanylyl cyclase (GC) in the nitric oxide-mediated signaling pathway?

    <p>Produces cGMP from GTP</p> Signup and view all the answers

    What is the effector molecule in the PI-3-Kinase (PI3K) → Akt system?

    <p>Akt</p> Signup and view all the answers

    What is the most common pathway associated with receptor tyrosine kinase (RTK) activation?

    <p>Ras-Raf-MAP kinase pathway</p> Signup and view all the answers

    Which molecule is the second messenger in the PI-3-Kinase (PI3K) → Akt system?

    <p>PIP3</p> Signup and view all the answers

    What is the result of PKG activity in many cases in the nitric oxide-mediated signaling pathway?

    <p>Smooth muscle relaxation</p> Signup and view all the answers

    What is the function of phospholipase C in the signaling pathway of receptor tyrosine kinases?

    <p>Conversion of PIP2 to IP3 and DAG</p> Signup and view all the answers

    What is the key mediator that relaxes smooth muscle in a wide variety of blood vessels and visceral organs?

    <p>NOs</p> Signup and view all the answers

    What is the function of Ras in the signaling cascade of receptor tyrosine kinases?

    <p>Activation of Raf</p> Signup and view all the answers

    What is the effector molecule in the PI-3-Kinase (PI3K) → Akt system?

    <p>Akt</p> Signup and view all the answers

    What happens when the concentration of the first messenger (ligand) increases in intracellular signaling?

    <p>Increased cytosolic calcium</p> Signup and view all the answers

    Which pathway is most commonly associated with RTK activation?

    <p>Ras-Raf-MAP kinase pathway</p> Signup and view all the answers

    What is the function of guanylyl cyclase (GC) in the nitric oxide-mediated signaling pathway?

    <p>Production of cGMP</p> Signup and view all the answers

    What molecule is phosphorylated by the receptor tyrosine kinase in the signaling process?

    <p>Tyrosine residues</p> Signup and view all the answers

    More Like This

    Enzyme Coupled Receptors
    20 questions

    Enzyme Coupled Receptors

    GodlikeWatermelonTourmaline avatar
    GodlikeWatermelonTourmaline
    Major Receptor Families Quiz
    6 questions
    Biochemistry: Enzyme-Coupled Receptors
    48 questions
    Use Quizgecko on...
    Browser
    Browser