Cell Signaling Pathways and Communication Methods Quiz

Cellular communication relies on the interaction between ______ signals and specific cell surface receptors

The mobilization of diffusible intracellular second-messenger systems is a secondary event triggered by the binding of ______ messengers to cell surface receptors

Hydrophobic messengers, such as ______ hormones, can diffuse across the plasma membrane and interact with cytosolic or nuclear receptors

Cells use a number of different, often intersecting ______ signaling pathways to ensure that the cell's response to a stimulus is tightly controlled

Early insight into signal transduction pathways was obtained from studies of the ______ system

Communication among cells is fundamental to all ______ processes, ranging from the induction of embryonic development to the integration of physiological responses in the face of environmental challenges

External signals such as odorants, chemicals that reflect metabolic status, ions, hormones, growth factors, and neurotransmitters can all serve as ______ messengers linking neighboring or distant cells

The classic definition of a hormone is a substance that is produced in one tissue or organ and released into the blood and carried to other organs (targets), where it acts to produce a specific ______.

The idea of endocrine or ductless glands developed from the recogni- tion that certain organs—such as the pituitary, adrenal, and thyroid gland—can synthesize and release specific chemical messengers in response to particular ______ states.

Receptors can be divided into four categories on the basis of their associated mechanisms of signal ______.

1. Ligand-gated ion channels. Integral membrane pro- teins, these hybrid receptor/channels are involved in sig- naling between electrically excitable ______.

2. G protein–coupled receptors. These integral plasma membrane proteins work indirectly—through an ______—to activate or to inactivate a separate mem- brane-associated enzyme or channel.

3. Catalytic receptors. When activated by a ligand, these integral plasma membrane proteins are either enzymes themselves or part of an ______ complex.

4. Nuclear receptors. These proteins, located in the cytosol or nucleus, are ______-activated transcription factors.

Second-messenger systems amplify signals and integrate responses among cell types. Once a signal has been received at the cell surface, it is typically amplified and transmitted to specific sites within the cells through ______.

For a molecule to function as a ______, its concentration, or window of activity, must be finely regulated.

The cell achieves this control by rapidly producing or activating the ______ messenger and then inactivating or degrading it.

To ensure that the system returns to a resting state when the stimulus is removed, ______ activities function at each step of the cascade.

The involvement of second messengers in catalytic cascades provides numerous opportunities to ______ a signal.

For example, the binding of a ligand to its receptor can generate hundreds of ______ molecules, which can in turn alter the activity of thousands of downstream effectors.

An example of such a cascade is the increased intracellular concentration of the second messenger ______.

Receptor occupancy activates a G protein, which in turn stimulates a membrane-bound enzyme, ______.

This enzyme catalyzes the synthesis of ______ from adenosine triphosphate (ATP), and a 5-fold increase in the intracellular concentration of ______ is achieved in approximately 5 seconds.

This sudden rise in cAMP levels is rapidly counteracted by its breakdown to adenosine 5’-monophosphate by ______.

Gap junctions facilitate the passage of inorganic ions and small molecules, such as Ca2+ and 3',5'-cyclic adenosine monophosphate (cAMP), from the cytoplasm of one cell into the cytoplasm of an adjacent cell. Mammalian gap junctions permit the passage of molecules that are less than _____ Da but restrict the movement of molecules that are greater than _____ Da.

The permeability of gap junctions can be rapidly regulated by changes in cytosolic concentrations of Ca2+, cAMP, and H+ as well as by the voltage across the cell membrane or membrane potential (Vm). This type of modulation is physiologically important for cell-to-cell _____

Adhering junctions form as the result of the Ca2+-dependent interactions of the extracellular domains of transmembrane proteins called _____

The clustering of cadherins at the site of interaction with an adjacent cell causes secondary clustering of intracellular proteins known as _____, which in turn serve as sites of attachment for the intracellular actin cytoskeleton.

Disruption of adhering junctions by certain growth factors causes _____ to dissociate from cadherin. The resulting rise in free _____ levels promotes the translocation of _____ to the nucleus. There, _____ regulates the transcription of multiple genes, including ones that promote cell proliferation and migration.

Tight junctions comprise transmembrane proteins that link with their counterparts on adjacent cells as well as intracellular proteins that stabilize the complex and also have a signaling role. The transmembrane proteins—including claudins, occludin, and junctional adhesion molecule—and their extracellular domains create the diffusion barrier of the tight junction. One of the integral cytoplasmic proteins in tight junctions, zonula occludin 1 (ZO-1), colocalizes with a serine/threonine kinase known as _____, which is found in certain renal tubule epithelial cells that reabsorb Na+ and Cl- from the tubule lumen.

Membrane-associated ligands provide spatial clues in migrating cells. For example, an ephrin ligand expressed on the surface of one cell can interact with an Eph receptor on a nearby cell. The resulting activation of the Eph receptor can in turn provide signals for regulating such developmental events as axonal guidance in the nervous system and endothelial cell guidance in the vasculature. This mechanism of direct cell communication involves the interaction of a receptor in the plasma membrane with a ligand that is itself a membrane protein on an adjacent cell, known as _____

Which one of these is the equation for a line in slope-intercept form?

Which one of these is the equation for a quadratic function?

Which one of these is the equation for an inverse function?

Which one of these is the equation for a square root function?

Which of the following is a characteristic of membrane-bound enzymes?

Which of the following is true about catalytic receptors?

What is the secondary event triggered by the binding of messengers to cell surface receptors?

What is the primary function of catalytic receptors?

What are the integral plasma membrane proteins involved in catalytic receptors?

What triggers the activation of catalytic receptors?

What is the primary function of membrane-bound enzymes?

Which type of messengers can diffuse across the plasma membrane and interact with cytosolic or nuclear receptors?

What do most chemical messengers interact with to trigger a cascade of secondary events?

What type of signaling pathways do cells use to ensure a tightly controlled response to a stimulus?

What type of messengers can serve as chemical messengers linking neighboring or distant cells?

What are the secondary events triggered by the binding of chemical messengers to cell surface receptors?

What type of proteins stabilize tight junctions and have a signaling role?

What type of receptors work indirectly to activate or inactivate a separate membrane-associated enzyme or channel?

Which of the following equations represents a linear function?

Which of the following is the equation of a parabola?

Which of the following equations represents an exponential function?

Which of the following equations represents an inverse function?

Which of the following equations represents a quadratic function?

Which of the following is NOT considered a chemical messenger in cellular communication?

Hydrophobic messengers, such as steroid hormones, can diffuse across the plasma membrane and interact with ______ receptors.

What type of signaling pathways do cells use to ensure a tightly controlled response to a stimulus?

Which of the following equations represents an exponential function?

What is the primary function of membrane-bound enzymes?

Receptors can be divided into four categories on the basis of their associated mechanisms of signal ______.

What is the secondary event triggered by the binding of messengers to cell surface receptors?

Which of the following is NOT one of the four categories of receptors based on their associated mechanisms of signal transduction?

What is the primary function of G protein–coupled receptors?

Which of the following is NOT a step in the signaling events initiated by plasma membrane receptors?

What type of messengers can diffuse across the plasma membrane and interact with cytosolic or nuclear receptors?

What are the secondary events triggered by the binding of chemical messengers to cell surface receptors?

Which of the following is NOT a characteristic of membrane-bound enzymes?

Receptor occupancy activates a G protein, which in turn stimulates a membrane-bound enzyme, ______.

Which of the following is a characteristic of second messengers?

What is the role of second messengers in signal transduction?

Which of the following is an example of a second messenger cascade?

What is the function of G protein in signal transduction?

Which of the following is true about ligands that activate the same signaling pathways in cells?

What is the role of second-messenger systems in a multicellular organism?

What triggers the activation of catalytic receptors?

What is the function of counterbalancing activities in second-messenger systems?

What allows ligands to produce distinct responses in different cells?

Which of the following is true about gap junctions?

What is the function of adhering junctions?

Which of the following is true about tight junctions?

Which of the following is true about membrane-associated ligands?

What is the primary function of catalytic receptors?

Which of the following is true about hydrophobic messengers?

What are the secondary events triggered by the binding of chemical messengers to cell surface receptors?

Which of the following is NOT a type of chemical messenger in cellular communication?

What is the primary function of membrane-bound enzymes?

Which of the following is the equation of a parabola?

What triggers the activation of catalytic receptors?

What is the function of G protein in signal transduction?

Which of the following equations represents an exponential function?

What is the secondary event triggered by the binding of messengers to cell surface receptors?

Which of the following is NOT a characteristic of second messengers?

What is the primary function of second messengers in signal transduction?

Which of the following equations represents a quadratic function?

What type of signaling pathways do cells use to ensure a tightly controlled response to a stimulus?

What are the integral plasma membrane proteins involved in catalytic receptors?

What is the function of adhering junctions?

What is the role of second messengers in signal transduction?

Which of the following equations represents an exponential function?

What allows ligands to produce distinct responses in different cells?

Which of the following is NOT a step in the signaling events initiated by plasma membrane receptors?

What do most chemical messengers interact with to trigger a cascade of secondary events?

2. G protein–coupled receptors. These integral plasma membrane proteins work indirectly—through an ______—to activate or to inactivate a separate mem- brane-associated enzyme or channel.

Gap junctions facilitate the passage of inorganic ions and small molecules, such as Ca2+ and 3',5'-cyclic adenosine monophosphate (cAMP), from the cytoplasm of one cell into the cytoplasm of an adjacent cell. Mammalian gap junctions permit the passage of molecules that are less than _____ Da but restrict the movement of molecules that are greater than _____ Da.

What are the secondary events triggered by the binding of chemical messengers to cell surface receptors?

Which one of these is the equation for a quadratic function?

Which of the following is NOT one of the four categories of receptors based on their associated mechanisms of signal transduction?

What type of messengers can diffuse across the plasma membrane and interact with cytosolic or nuclear receptors?

Which of the following is true about adhering junctions?

What is the primary function of gap junctions?

Which of the following is a characteristic of tight junctions?

What is the function of membrane-associated ligands?

Which of the following is NOT a mechanism by which cells can directly communicate?

How are gap junctions regulated?

What is the role of adhering junctions in organ development and remodeling?