Cell Signalling and Transduction
The signaling molecules called steroid hormones

are hydrophilic and so cannot penetrate the plasma membrane
never enter the blood of humans
are made in one location of the body but have their effects some distance away
bind to cell surface receptors to trigger chemical cascades

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
Two key organizing principles for large multicellular organisms are

prokaryotic cell structure and cell specialization
communication between cells and simple nerve reflexes
simple nerve reflexes and cell specialization
cell specialization and communication between cells

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
Nitroglycerin has long been administered to human patients suffering from chronic chest pain (angina). This medication works because it

breaks down into nitric oxide, which increases blood flow to the heart
interferes with chemical cascades that trigger contraction of heart muscle
is broken down into hormones that affect the heart
mimics the action of signal receptors

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
The binding of ligands to many G-proteins linked receptors leads to shortlived

decrease in the concentration of certain extracellular signaling molecules called first messenger
increase in the concentration of certain extracellular signaling molecules called first messenger
increase in the concentration of certain intracellular signaling molecules called second messenger
decrease in the concentration of certain intracellular signaling molecules called second messenger

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
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
None of these
Because nitric oxide cannot cross cell membranes and enter the blood
Because other body tissues use a different signaling molecule

ANSWER DOWNLOAD EXAMIANS APP