Signal Transduction I Flashcards
Are signal transactions slow or quick?
The actual extracellular binding may be quick, but may have long lasting effects
Where is cortisol made?
adrenal gland
cortisol, estradiol, and testosterone are all classified as what kinds of secretions?
steroids (derivatives of cholesterol)
What cells are affected by paracrine signals?
nearby cells (local)
Are neuronal signals specific?
Yes, they are relayed through a nerve fiber to a specific cell- neurotransmitters
Why is signal tranduction considered an amplification event?
Binding of the first messenger stimulates the release of lots of secondary messengers
When do proteins act as binary switches?
When the off/on conformation of a protein is dependent on the environment and possibly binding of messengers
Which aspect of signal transductions, intracellular or extracellular signaling is faster
extracellular
Is signal transduction that alters protein function fast or slow compared to the transduction that alters protein synthesis?
Yes (seconds to minutes), while proteins synthesis alteration takes (mins- hrs)
What kinds of the first messenger receptors are extracellular in nature?
cytokine, GPCR, tyrosine kinase (has a large, hydrophilic signal)
What kinds of the first messenger receptors are intracellular in nature?
steroids (has a small, hydrophobic signal)
What effect do antagonist ligands have on receptors?
They only work to block the action of the receptor. I.e. they neutralize the receptor so no signal transduction can occur
What is the rank of potency for B1 adrenergic receptors
Iso >Epi=Norepi
What is the rank of potency for B2 adrenergic receptors
Iso>Epi>Norepi
What is the rank of potency for B3 adrenergic receptors
Iso=Norepi> Epi
