Small charged molecules, often biogenic amines function as none of these neurotransmitters hormones both (a) and (b) TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following is a hormone whose action requires a cell surface receptor? Growth factors Progesterone Nitric oxide Adrenaline TRUE ANSWER : ? YOUR ANSWER : ?
Two key organizing principles for large multicellular organisms are simple nerve reflexes and cell specialization communication between cells and simple nerve reflexes cell specialization and communication between cells prokaryotic cell structure and cell specialization TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following statements about G proteins is false? They are involved in signal cascades They must be active before the cell can make needed cAMP They bind to and are regulated by guanine nucleotides They become activated when bound to GDP TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following is a second messenger? Both (a) and (b) lnositol 1,4,5-triphosphate Phospholipase C Diacyl glycerol TRUE ANSWER : ? YOUR ANSWER : ?
If a disease of the blood vessels caused the endothelial cells of the vessel to die, what effect would that have on the cellular activities associated with vasodilation? It would be more difficult to increase blood flow and reduce blood pressure All of these Nitric oxide would no longer be produced Smooth muscle cells could not be made to relax TRUE ANSWER : ? YOUR ANSWER : ?
Why is it that inhaling nitric oxide reduces blood pressure only in the lung tissue and not elsewhere in the body*? Because nitric oxide breaks down quickly and thus cannot travel far Because nitric oxide cannot cross cell membranes and enter the blood None of these Because other body tissues use a different signaling molecule TRUE ANSWER : ? YOUR ANSWER : ?
The binding of ligands to many G-proteins linked receptors leads to shortlived increase in the concentration of certain extracellular signaling molecules called first messenger decrease in the concentration of certain intracellular signaling molecules called second messenger increase in the concentration of certain intracellular signaling molecules called second messenger decrease in the concentration of certain extracellular signaling molecules called first messenger TRUE ANSWER : ? YOUR ANSWER : ?
Self-phosphorylation is an excellent mechanism for triggering specific catalytic function of the proteins involved in signal cascades because it makes the receptor more likely to capture the signaling, molecule None of these allows hydrophilic signaling molecules to cross the plasma membrane changes the shape and thus the enzymatic activity of the proteins involved TRUE ANSWER : ? YOUR ANSWER : ?
The signaling molecules called steroid hormones are made in one location of the body but have their effects some distance away are hydrophilic and so cannot penetrate the plasma membrane never enter the blood of humans bind to cell surface receptors to trigger chemical cascades TRUE ANSWER : ? YOUR ANSWER : ?