Chapter 9 Based on assignment
Put the stages of cell signaling in the correct order.
1. receptor actoivation 2. signal transduction 3. cellular response
Signal transduction is the_____ stage of cell signaling.
2nd
Contact-dependent signaling matches
A membrane-bound signaling molecule binds to a receptor on the surface of another cell.
What does the binding of a signaling molecule to its receptor stimulate?
A signal transduction pathway
Endocrine signaling
A signaling molecule acts on target cells distant from the cell that secreted the signa
Paracrine signaling
A signaling molecule affects target cells nearby but not the cell that secreted the signal.
Autocrine signaling
A signaling molecule binds to a receptor on the same cell that secreted the signal.
Receptor activation
A signaling molecule binds to a receptor.
During cellular signaling, what event causes the receptor to become activated?
A signaling molecule binds to it.
Direct intercellular signaling
A signaling molecule passes between the cytosol of adjacent cells through a cell junction.
Cellular response
An enzyme, structural protein, or transcription factor is altered.
What is another name for programmed cell death?
Apoptosis
Identify the signaling process that stimulates a response by secreting signaling molecules that bind to receptors on the cell's own surface.
Autocrine signaling
Signals influence the behavior of cells by interacting with receptors to elicit what type of response?
Cellular
Which of the following are examples of cell-to-cell signaling?
Contact-dependent signaling Direct intercellular signaling Paracrine signaling Endocrine signaling
Which of the following is a hormone that activates the enzyme adenylyl cyclase?
Epinephrine
True or false: Some living cells do not conduct and require cell communication to survive.
False
Binding of the α subunit of a(n) ______ ______ stimulates the enzyme adenylyl cyclase to synthesize cAMP.
G : protein
What type of receptor mediates the signal transduction pathway associated with cAMP?
G protein
In the signal transduction pathway involving cAMP, the hormone epinephrine first binds to its receptor and activates a _____ protein. The alpha subunit then activates the enzyme adenylyl _____ which catalyzes the production of cAMP from ATP.
G; cyclase
Name the protein ligand that acts as a signaling molecule that stimulates cell division.
Growth factor
Where are cell surface receptors found?
In the plasma membrane
Identify the stage of cell signaling where a signaling molecule binds to a receptor, causing a conformational change in the receptor.
Receptor activation
True or false: The mode of communication between two cells depends in part on the distance between the cells.
T
The equation, kon [Ligand] + [Receptor] ⇆ [Ligand - Receptor complex] koff, illustrates how a ligand-receptor complex is formed. In this equation, what do the brackets represent?
The concentration
The equation, kon [Ligand] + [Receptor] ⇌ [Ligand - Receptor complex] koff, illustrates how a ligand-receptor complex is formed. In this equation, what does the kon represent?
The rate at which binding occurs
Signal transduction matches
The signal is converted to a different type of signal, often resulting in the production of an intracellular signaling molecule.
How do second messengers amplify cellular signaling?
They allow many more target proteins to be activated.
True or false: The function of apoptosis is to ensure a proper number of cells in the body and to eliminate worn out or potentially harmful cells.
True
Because the binding of a ligand is a reversible process, once the ligand is released, the receptor is no longer:
activated
Cyclic AMP is synthesized by the enzyme
adenylyl cyclase
Cyclic AMP is synthesized by:
adenylyl cyclase
The synthesis of cAMP occurs when one type of G protein α subunit interacts with the enzyme
adenylyl cyclase
The main advantage of second messengers in cellular signaling are that they ___ the original signal and increase the ___ of intracellular signaling.
amplify ; speed
The enzyme adenylyl cyclase, which synthesizes cAMP, is stimulated by:
binding of the α subunit of a G protein
The GPCR mediates the signal transduction pathway involving _____ which is synthesized by activated adenylyl cyclase.
cAMP
The interaction between the α subunit of an appropriate G protein and adenylyl cyclase causes adenylyl cyclase to synthesize:
cAMP
Which of the following is a second messenger?
cAMP
One reason for cell signaling is for cells to communicate with each other. This type of communication is called:
cell-to-cell
Signals influence the behavior of _____ nearby or at long distances by interacting with receptors to elicit a response.
cells
Cell signaling is important because:
cells need to communicate with each other. cells need to respond to a changing environment.
Apoptosis is an example of what type of response involving cell communication?
cellular
When a ligand alters the structure of its receptor, the conformational change that occurs activates a(n)
cellular
Both incoming signal and outgoing signals are important in the process of cell ________ , which is also called cell signaling.
communication
During receptor activation the binding of a signaling molecule causes a ______ change in a receptor that activates its function.
conformational
During the receptor activation stage of cell signaling, the _____ that occurs in the receptor activates its function.
conformational
When ligands alter the structure of their receptors, this causes a(n):
conformational change
Second messengers increase the speed of cellular signaling because they:
diffuse through the cytosol rapidly
Unlike enzymes, which convert their substrates into products, receptors typically:
do not alter the structure of their ligands
Cell-to-cell communication can occur between cells in five common ways. This figure depicts _____ signaling.
endocrine
Cell signaling allows cells to detect and respond to signals from their and from other cells.
environment
EGF is a protein that stimulates the ____ cells to divide
epidermal
True or false: A signal transduction pathway consists of carbohydrate molecules.
false
A(n) ________ factor is a protein ligand that acts as a signaling molecule that stimulates cell growth or division.
growth
Signaling molecules that promote cell division are called
growth factors
Second messengers relay signals:
inside the cell
In some cases, a signaling molecule must first pass through the plasma membrane before activating a receptor. The receptors activated by these molecules are called:
intracellular receptors
What term is used to describe a signaling molecule?
ligand
When a(n) ______ binds to its receptor, it causes a conformational change in the receptor.
ligand
Plant cells produce hormones that determine the pattern of cell elongation so the plant will grow toward light. The hormone effect is an example of an
outgoing signal
In what type of signaling does a specific cell produce a signaling molecule that does not affect the cell secreting the signal but influences the behavior of target cells in close proximity?
paracrine
Cell surface receptors are receptors that are embedded in the
plasma membrane
What forms a signal transduction pathway?
proteins
Proteins that interact with signaling molecules are called _____. These proteins can be located on the cell surface or inside the cell.
receptors
Small molecules or ions that relay signals inside the cell are called
second
cAMP is an example of a(n) _____ messenger.
second
One of the advantages of _______ _______ such as cAMP is speed. Because they are relatively small and water-soluble, they can diffuse rapidly through the cytosol.
second messengers
A ligand is also known as a(n) ______ molecule
signal
Identify the stage of cell signaling where the initial signal is converted to a different signal inside the cell.
signal transduction
A growth factor is a type of:
signaling molecule
Cell communication, also called cell ______, involves both incoming and outgoing signals.
signalling
EGF stimulates the division of:
skin cells
The mode of cell communication depends on:
the distance between the cells that need to communicate
The effect of signaling molecules on cells occurs through signal transduction pathways that ultimately control the:
the functions and or synthesis of specific proteins
Cell communication is an important function for maintaining a balance in the internal environment of organisms. To maintain this equilibrium, cells must detect and respond to signals from:
their environment other cells
Cell signaling has several stages. Cells respond to signals in the ______ stage.
third
What is the second stage of cell signaling?
transduction
When a signaling molecule binds to its receptor, it stimulates a signal ____ pathway
transduction
what is the second stage of cell signaling
transduction
Signaling molecules exert their effects on cells through signal
transduction pathways
An example of an incoming signal in cell communication is:
ultraviolet light