if you want to remove an article from website contact us from top.

    which component of the signal transduction pathway in rod cells is found in the cytosol of the cell?

    James

    Guys, does anyone know the answer?

    get which component of the signal transduction pathway in rod cells is found in the cytosol of the cell? from EN Bilgi.

    Solved Which component of the signal transduction pathway in

    Answer to Solved Which component of the signal transduction pathway in

    © 2003-2022 Chegg Inc. All rights reserved.

    Source : www.chegg.com

    Ch. 38 Bio HW Flashcards

    Start studying Ch. 38 Bio HW. Learn vocabulary, terms, and more with flashcards, games, and other study tools.

    Ch. 38 Bio HW

    5.0 1 Review

    Which component of the signal transduction pathway in rod cells is found in the cytosol of the cell?

    Click card to see definition 👆

    cGMP

    Click again to see term 👆

    During signal transduction in a rod cell, the sensory signal is amplified when

    Click card to see definition 👆

    Phosphodiesterase catalyzes cGMP hydrolysis.

    Click again to see term 👆

    1/55 Created by SydneyBug2002

    Terms in this set (55)

    Which component of the signal transduction pathway in rod cells is found in the cytosol of the cell?

    cGMP

    During signal transduction in a rod cell, the sensory signal is amplified when

    Phosphodiesterase catalyzes cGMP hydrolysis.

    Unlike signal transduction in many other sensory receptors, signal transduction in rods

    Results in hyperpolarization of the sensory cell.

    Suppose a mutation greatly increases the affinity of a rod's sodium channels for cGMP, such that once cGMP binds to a channel, it remains bound for much longer than normal. What would be the effect of this mutation on the rod's sodium channels?

    The sodium channels would remain open longer, even when cGMP decreases after light stimulation.

    Suppose an individual had a mutation that decreased the enzymatic activity of phosphodiesterase in rod cells. What would be the effect of this mutation on the rod cells?

    A smaller hyperpolarization of the rod would occur.

    Cephalization, the clustering of neurons and interneurons in the anterior part of the animal, is apparent in

    Planaria

    Which description of a glial cell and its function is correct?

    Astrocytes−−metabolize neurotransmitters and modulate synaptic effectiveness

    The cerebrospinal fluid is

    A filtrate of the blood.

    The blood-brain barrier

    Filters the entry of solutes from the blood into the cerebrospinal fluid.

    What type of neuron would be abundant in the white matter in the brain and the white matter in the spinal cord?

    Myelinated axon

    The divisions of the nervous system that have antagonistic, or opposing, actions are the

    Sympathetic and parasympathetic systems

    Preparation for the "rest and digest" response includes activation of the ________ nervous system.

    Parasympathetic

    Suppose you were walking to class when all of a sudden your friend jumped out and scared you! What would you expect to observe with your nervous system?

    Increased activity in the sympathetic division and decreased activity in the parasympathetic division

    The activation of the parasympathetic branch of the autonomic nervous system is associated with

    Resting and digesting

    What nervous system components would you expect to find in a cephalized invertebrate such as a beetle?

    A brain, ventral nerve cords, and segmental ganglia

    Afferent neuronal systems include the

    Sensory systems

    Imagine you are resting comfortably on a sofa after dinner. This could be described as a state with

    Decreased activity in the sympathetic nervous system and increased activity in the parasympathetic and enteric nervous systems.

    An organism that lacks neurons that perform integration

    Will not be able to interpret stimuli.

    The system that modulates excitation and inhibition of the smooth and cardiac muscles of the digestive, cardiovascular, and excretory systems is the

    Autonomic nervous system

    Which examples correctly illustrate the cooperation between the motor and nervous systems to maintain homeostasis in a vertebrate body?

    A drop in body temperature leads to shivering and constriction of surface blood vessels

    Injury to just the hypothalamus would most likely disrupt __________.

    Regulation of body temperature

    What vertebrate brain structure coordinates the biological clock?

    Hypothalamus

    The endogenous nature of biological rhythms is based on the observation that animals isolated from light and dark cues

    Continue to have cycles of approximately 24 hours in duration−−some more rapid, some slower.

    The bottlenose dolphin breathes air but can sleep in the ocean because it

    Alternates which half of its brain is asleep and which half is awake.

    Which of the following structures are correctly paired?

    Hindbrain and cerebellum

    The coordination of groups of skeletal muscles is driven by activity in the

    Cerebellum

    Hormones that are secreted by the posterior pituitary gland are made in the

    Hypothalamus

    The regulation of body temperature derives from the activity of the

    Hypothalamus

    The regulatory centers for the respiratory and circulatory systems are found in the

    Medulla oblongata

    Suppose a person could go days between eating but not feel hungry. What part of his or her brain may be affected?

    Hypothalamus

    How does fMRI measure brain activity?

    By measuring changes in oxygen concentration

    Sheila is a 29-year-old female who suffered a brain injury in a car accident. After the accident she had trouble with calculation, contemplation, and cognition. What part of the brain did Sheila likely injure?

    Cerebrum

    The motor cortex is part of the

    Cerebrum

    In mammals, advanced cognition is usually correlated with a large and very convoluted cerebral cortex, but birds are capable of sophisticated cognition because they have

    Source : quizlet.com

    Pathways of Intracellular Signal Transduction

    Most cell surface receptors stimulate intracellular target enzymes, which may be either directly linked or indirectly coupled to receptors by G proteins. These intracellular enzymes serve as downstream signaling elements that propagate and amplify the signal initiated by ligand binding. In most cases, a chain of reactions transmits signals from the cell surface to a variety of intracellular targets—a process called intracellular signal transduction. The targets of such signaling pathways frequently include transcription factors that function to regulate gene expression. Intracellular signaling pathways thus connect the cell surface to the nucleus, leading to changes in gene expression in response to extracellular stimuli.

    An official website of the United States government

    Log in Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation Bookshelf

    Browse Titles Advanced

    Help

    By agreement with the publisher, this book is accessible by the search feature, but cannot be browsed.

    The Cell: A Molecular Approach. 2nd edition.

    Show details

    Pathways of Intracellular Signal Transduction

    Most cell surface receptors stimulate intracellular target enzymes, which may be either directly linked or indirectly coupled to receptors by G proteins. These intracellular enzymes serve as downstream signaling elements that propagate and amplify the signal initiated by ligand binding. In most cases, a chain of reactions transmits signals from the cell surface to a variety of intracellular targets—a process called intracellular signal transduction. The targets of such signaling pathways frequently include transcription factors that function to regulate gene expression. Intracellular signaling pathways thus connect the cell surface to the nucleus, leading to changes in gene expression in response to extracellular stimuli.

    Go to:

    The cAMP Pathway: Second Messengers and Protein Phosphorylation

    Intracellular signaling was first elucidated by studies of the action of hormones such as epinephrine, which signals the breakdown of glycogen to glucose in anticipation of muscular activity. In 1958, Earl Sutherland discovered that the action of epinephrine was mediated by an increase in the intracellular concentration of cyclic AMP (cAMP), leading to the concept that cAMP is a second messenger in hormonal signaling (the first messenger being the hormone itself). Cyclic AMP is formed from ATP by the action of adenylyl cyclase and degraded to AMP by cAMP phosphodiesterase (Figure 13.18). As discussed earlier, the epinephrine receptor is coupled to adenylyl cyclase via a G protein that stimulates enzymatic activity, thereby increasing the intracellular concentration of cAMP (see Figure 13.11).

    Figure 13.18

    Synthesis and degradation of cAMP. Cyclic AMP is synthesized from ATP by adenylyl cyclase and degraded to AMP by cAMP phosphodiesterase.

    How does cAMP then signal the breakdown of glycogen? This and most other effects of cAMP in animal cells are mediated by the action of cAMP-dependent protein kinase, or protein kinase A, an enzyme discovered by Donal Walsh and Ed Krebs in 1968. The inactive form of protein kinase A is a tetramer consisting of two catalytic and two regulatory subunits (Figure 13.19). Cyclic AMP binds to the regulatory subunits, leading to their dissociation from the catalytic subunits. The free catalytic subunits are then enzymatically active and able to phosphorylate serine residues on their target proteins.

    Figure 13.19

    Regulation of protein kinase A. The inactive form of protein kinase A consists of two regulatory (R) and two catalytic (C) subunits. Binding of cAMP to the regulatory subunits induces a conformational change that leads to dissociation of the catalytic (more...)

    In the regulation of glycogen metabolism, protein kinase A phosphorylates two key target enzymes (Figure 13.20). The first is another protein kinase, phosphorylase kinase, which is phosphorylated and activated by protein kinase A. Phosphorylase kinase in turn phosphorylates and activates glycogen phosphorylase, which catalyzes the breakdown of glycogen to glucose-1-phosphate. In addition, protein kinase A phosphorylates the enzyme glycogen synthase, which catalyzes glycogen synthesis. In this case, however, phosphorylation inhibits enzymatic activity. Elevation of cAMP and activation of protein kinase A thus blocks further glycogen synthesis at the same time as it stimulates glycogen breakdown.

    Figure 13.20

    Regulation of glycogen metabolism by protein kinase A. Protein kinase A phosphorylates both glycogen synthase and phosphorylase kinase. Glycogen synthase (which catalyzes glycogen synthesis) is inhibited by this phosphorylation, whereas phosphorylase (more...)

    The chain of reactions leading from the epinephrine receptor to glycogen phosphorylase provides a good illustration of signal amplification during intracellular signal transduction. Each molecule of epinephrine activates only a single receptor. However, each receptor may activate up to a hundred molecules of Gs. Each molecule of Gs then stimulates the enzymatic activity of adenylyl cyclase, which can catalyze the synthesis of many molecules of cAMP. Signal amplification continues as each molecule of protein kinase A phosphorylates many molecules of phosphorylase kinase, which in turn phosphorylate many molecules of glycogen phosphorylase. Hormone binding to a small number of receptors thus leads to activation of a much larger number of intracellular target enzymes.

    In many animal cells, increases in cAMP activate the transcription of specific target genes that contain a regulatory sequence called the cAMP response element, or CRE (Figure 13.21). In this case, the signal is carried from the cytoplasm to the nucleus by the catalytic subunit of protein kinase A, which is able to enter the nucleus following its release from the regulatory subunit. Within the nucleus, protein kinase A phosphorylates a transcription factor called CREB (for CRE-inding protein), leading to the activation of cAMP-inducible genes. Such regulation of gene expression by cAMP plays important roles in controlling the proliferation, survival, and differentiation of a wide variety of animal cells.

    Source : www.ncbi.nlm.nih.gov

    Do you want to see answer or more ?
    James 9 month ago
    4

    Guys, does anyone know the answer?

    Click For Answer