Cell Communcation Homework flashcards

What are the distance requirements for cells to communicate with one another through endocrine signaling?

They may be distant from one another.

In Blank______ signaling, the cell that secretes messenger molecules also produces receptors in order to stimulate a response.

autocrine

Cellular signaling involves an interaction between a signaling molecule from one cell and a(n) _____ protein on or in another cell.

receptor

In Blank______ signaling, a cell produces a signal to induce changes in nearby cells.

paracrine

Which signaling process occurs when cells release signals that travel long distances through the blood of a vertebrate or the vascular system of a plant?

Endocrine signaling

Which type of signaling mechanism occurs between cells at a great distance from one another?

Endocrine

If a cell secretes a signal that binds to its own receptors or those of neighboring cells of the same type, the process is called_____ signaling

autocrine

What is the second stage of cell signaling?

Signal transduction

During cellular signaling, what event causes the receptor to become activated?

A signaling molecule binds to it.

One type of signaling involves a specific cell producing a signaling molecule that does not affect the cell secreting the signal but influences the behavior of target cells in close proximity. This type of signaling is called ______ signaling.

paracrine

The type of signaling whereby cells produce hormones that travel long distances or even diffuse through the air to affect other cells is termed ___ signaling.

endocrine

The last stage of a cell signaling pathway is the cellular ____

response

Receptor activation

A signaling molecule binds to a receptor.

Signal transduction

The signal is converted to a different type of signal, often resulting in the production of an intracellular signaling molecule.

Cellular response

An enzyme, structural protein, or transcription factor is altered.

The stage of cell signaling that immediately follows receptor activation is called signal

transduction

Receptor____ is the initial stage of cell signaling.

activation

During the receptor activation stage of cell signaling, a signaling molecule binds to a receptor and causes a(n) change in the ____ receptor.

conformational

A ligand is also known as a(n) _____ molecule.

signaling

What is the third and final stage of cell signaling?

Cellular response

When ligands alter the structure of their receptors, this causes a(n):

conformational change

Put the steps involved in a cell-to-cell signaling pathway in the correct order. Start with the earliest at the top.

binding of a signaling molecule to receptor, intracelluar signal transduction pathway, cellular response

In a ligand-receptor complex, what term stands for dissociation constant?

K_d

Identify the stage of cell signaling where a signaling molecule binds to a receptor, causing a conformational change in the receptor.

activation

The formula ____=______ , represents a ligand concentration where half of the receptors have bound ligands.

K_d = Ligand

What term is used to describe a signaling molecule?

Ligand

Where are cell surface receptors found?

In the plasma membrane

A conformational change in the receptor occurs after a(n) ____ binds to it.

ligand

Which of the following are types of cell surface receptors?

• Enzyme-linked receptor

• Ligand-gated ion channel

• G-protein-coupled receptor

The change that occurs when a signaling molecule binds to the extracellular domain of an enzyme-linked receptor causes the catalytic domain to become Blank______.

active

K_d is called the _____ _____between a ligand and its receptor.

dissociation constant

Intracellular domain

Catalytic function

Extracellular domain

Signal-binding function

Cell surface receptors are receptors that are embedded in the ______ membrane.

plasma

What happens when a ligand binds to the extracellular domain of an enzyme-linked receptor?

The catalytic domain of the receptor becomes activated

The three categories of cell surface receptors are: ____ linked receptors, ____ protein-coupled receptors, and ____gated ion channels.

Enzyme,G, Ligand

The majority of enzyme-linked receptors function as Blank______.

protein kinases

When a signaling molecule binds to an enzyme-linked receptor, a conformational change is transmitted through the membrane-embedded portion of the protein. This conformational change causes the intracellular _____ domain to become active.

catalytic

The enzymes that transfer a phosphate group from ATP to specific amino acids in a protein are known as protein

kinases.

The Blank______ domain of enzyme-linked receptors binds a signaling molecule, whereas the Blank______ domain of enzyme-linked receptors has a catalytic function.

extracellular ; intracellular

An enzyme that adds a phosphate group to the amino acid tyrosine on proteins is called a tyrosine _____

kinase

he catalytic domain of an enzyme-linked receptor is activated upon binding of a(n) _____ to the extracellular domain.

ligand

G-protein-coupled receptors interact with

intracellular G protein

G proteins are so named because of their ability to bind:

GTP and GDP

What is the function of protein kinases?

They add phosphate groups to proteins.

GTP refers to guanosine triphosphate and GDP stands for guanosine diphosphate.

true

What type of molecule does the extracellular domain of an enzyme-linked receptor bind?

A signaling molecule

When a GPCR is activated, it causes the G protein to release _____ and bind_____ .

GDP, GTP

Tyrosine kinases attach a(n) Blank______ group to specific tyrosines on proteins.

phosphate

The binding of a signaling molecule activates:

GPCR

The G protein binds to

GTP

The α subunit dissociates from

β/γ dimer.

Identify intracellular proteins that bind guanosine triphosphate (GTP) and guanosine diphosphate (GDP).

G proteins

Select the event that occurs last after the activation of a G-protein coupled receptor

A G protein hydrolyzes GTP to GDP.

What proteins can bind GTP and GDP?

G proteins

What event must occur before a G protein can return to its inactive state?

The GTP must be hydrolyzed to GDP.

The acronym GDP stands for

guanosine diphosphate

Which of the following allow the diffusion of ions across cellular membranes?

Ion channels

What happens to the G protein after a GPCR is activated?

It releases GDP and binds GTP.

Ligand-gated ion channels permit _____ to pass through the plasma membrane.

ions

In the first step of the signal transduction pathway involving cAMP, a signal molecule binds to and activates a receptor called______ This causes a G protein to bind _____which promotes the dissociation of the α subunit from the β/γ dimer.

GPCR, GTP