openstax bio Chapt 9
what is the function of phosphatase
a phorphatase removes the phosphate group from ph
apoptosis can occur in a cell when the cell
damaged, no longer needed, infected by a virus
the secretion of hormones by the pituitary gland is an example of
endocrine signaling
what is the effect of an inhibitor binding an enzyme
enzyme is inactivated
why are ion channels neccessary to transport ions into or out of a cell
ions are charged particles and cannot diffuse thro the hydrophobic interior of the membrane
Which type of molecule acts as a signaling molecule in yeasts
mating factors
how does NF-kB induce gene expression
phosphorylations of the inhibitor Ik-B dissociates the complex between it and NK-kB and allows NF-kB to enter the nucleus and stimulate transcripation
Quorum sensing is triggered to begin when___
sufficient numbers of bacteria are present
Endocrine signal are transmitted more slowly than paracrine signal because
the ligands are transported thro the bloodstream and travel greater distances
What property prevents the ligands of cell-surface receptors from entering the cell?
the molecules are hydrophilic and cannot penetrate the hydrophobic interior of the plasma membrane
where do DAG and IP3 originate
they are the cleavage product of the inositol phospolipid PIP2
What property enables the residues of the amino acids serine, threonine, and tyrosine to be phosphorylated
they contain hydroxyl group
