module 9: cell signaling

Which of the following types of cell signaling is long range and uses hormones as signals?

endocrine

The fastest response following activation of a G protein-coupled receptor would occur when an activated G protein what?

activates ion channel

Which of the following correctly matches a G protein-activated enzyme with the second messenger molecule it produces?

phospholipase C; diacylglycerol

Which of the following describes negative feedback regulation?

a component late in the pathway inhibits an enzyme early in the pathway

Internal receptors bind to small ? molecules and can be found in the ??

hydrophobic, cytosol and nucleus

Which of the following depicts the correct order of steps involved in nitric oxide (NO) signaling to trigger smooth muscle relaxation?

acetylcholine receptor activation > NO synthetase > NO diffusion > activation of guanylyl cyclase > cGMP production

Which type of external receptor exhibits the slowest signal transduction? This results from receptor binding often leading changes in gene expression.

enzyme-coupled receptors

Delta-Notch signaling is an example of what type of cell signaling?

direct

Multiple signaling pathways can interaction with one another to coordinate cell activities. What do we call this phenomenon?

cross-talk

A signaling molecule can only have an effect if a target cell has what?

receptors for that signaling molecule

what are the four components of signal tranduction?

signaling cell, ligands, receptors, target cells

proteins, peptides, hormones, gases, steroids, FA derivatives are examples of what?

ligands

target cells must have ??? for an effect.

signaling molecule receptor

true/false: one signal can modify another

true

which type of signal involves cell interaction through physical contact or by cell-to-cell binding of surface molecules?

direct

which type of signal involves cell communication that release signaling molecules that affect only nearby cells?

paracrine

which type of signal involves cell communication that cell secretes a signaling molecule that minds to receptors on its own surface, influencing its own behavior?

autocrine

the only way for a cell to respond to a signaling molecule is to have a ?

receptor

glucocorticoids bind to ?? which then translocates to the ? and alters transcription through ???.

receptor dimer, nucleus, direct DNA binding

Thyroid hormone bind to ? in the ?.

receptor, nucleus

in the absence of hormones, thyroid hormone receptors bound to ?? that inhibit gene transcription. once a hormone is added, the compressor gets ? and becomes a ?

DNA compressor, released, coactivator (HAT)

which external receptor involves ligand binding that changes the receptor in the channel to let in ions into the cytosol?

ion channel coupled

? receptors causes immediate responses like muscle contraction by allowing ion flow while ? receptors initiate slower, more diverse signaling cascade that leads to gene expression.

nicotinic, muscarinic

which external receptor is the largest and interacts with ion channel very rapidly?

g protein coupled

in g protein coupled receptors, interaction with enzymes is more ?. activation of enzyme produces many ?? that interact with effector proteins.

complex, second messengers

epinephrine targets ?? and the major response is ??.

skeletal muscle, glycogen breakdown

what is another correct pair that matches a G protein-activated enzyme with the second messenger molecule it produces?

adenylyl cyclase, cAMP

true/false: all second messengers are hydrophilic.

false

what is an example of a hydrophobic second messenger?

nitric oxide

intracellular signaling cascades allow ? of incoming signals and ? to changes in concentration of signaling molecules.

amplification, adapt

what acts as primary transducers of extracellular signals to the intracellular environment?

RTKs

what mediates intracellular signals resulting from activation of associated cell surface receptors?

nRTKs

Dimerization brings the intracellular kinase domains to cross-phosphorylate that activates the kinase domain

RTKs

JAKs, Src family kinases are activated through trans-autophosphorylation or phosphorylation by other associated kinases

nRTKs

what factor signaling is activated by IKB and is involved in inflammation cell proliferation, cytokines, growth factors, infectious antigens, DNA damage?

NFKB

what factor signaling is involved to stabilize transcription factor β-catenin?

Wnt

? targets STAT proteins that leads to phosphorylation

JAK

? translocates to the nucleus and initiates transcription.

STAT

? binds to receptors that phosphorylates serine or threonine. 

TGF-beta