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