Open Question
Some hormones act bya. increasing the synthesis of enzymes,b. converting an inactive enzyme into an active enzyme,c. affecting only specific target organs,d. all of these.
16. The Endocrine System
Membrane Bound Receptors and Secondary Messengers
Back16. The Endocrine System
Membrane Bound Receptors and Secondary Messengers
- Multiple Choice
What is the role of G proteins in GPCR signaling?
- Multiple Choice
Hormones can bring about substantial physiological changes at very low concentrations. How does this relate to the concept of second messenger systems?
- Multiple Choice
You are studying how a hormone affects a cell and find that when oxytocin binds the receptor, the intracellular concentration increases. Based on this information, what could you logically conclude about this cell and hormone?
- Multiple Choice
cAMP, , and DAG are all molecules that are used as secondary messengers. Which statement below correctly identifies a difference between the pathways in which they are found?
- Multiple ChoiceSteroid hormones influence cellular activities by __________.
- Multiple ChoiceWhich of the following describes a hormone that CANNOT exhibit its full effect without the presence of another hormone?
- Multiple ChoiceHow do protein kinases affect enzymes?
- Multiple ChoiceWhich of the following is true about water-soluble hormones?
- Multiple ChoiceThe transcription of new messenger RNA is a function of __________.
- Open QuestionCyclic AMP functions as a second messenger to (a) build proteins and catalyze specific reactions, (b) activate adenylate cyclase, (c) open ion channels and activate key enzymes in the cytoplasm, (d) bind the hormone–receptor complex to DNA segments.
- Open QuestionHow would blocking the activity of phosphodiesterase (PDE) affect a cell that responds to hormonal stimulation by the cAMP second messenger system?
- Open QuestionA researcher observes that stimulation by a particular hormone induces a marked increase in the activity of G proteins in the target plasma membrane. The hormone being studied is probably (a) a steroid, (b) a peptide, (c) testosterone, (d) estrogen, (e) aldosterone.