Conduction has to be touching the two objects. Convection is not direct.
According to Ptolemy's model, he, too, believed in a geocentric Universe and that the planets and stars were perfect spheres, though Earth itself was not.
He further thought that the movements of the planets and stars must be circular since they were perfect and, if the motions were circular, then they could go on forever.
<h3>What is comets and shooting stars?</h3>
Shooting stars are very different from comets, although the two can be related. A Comet is a ball of ice and dirt, orbiting the Sun (usually millions of miles from Earth). ... A shooting star on the other hand, is a grain of dust or rock (see where this is going) that burns up as it enters the Earth's atmosphere.
Learn more about ptolemy's model:
brainly.com/question/12639459
This has to do with independent and dependent variables. The independent variable is what affects the dependant variable, so the question is, does a students mark on a test affect their hours of sleep or does their hours of sleep affect their test results? Which one makes more sense? I would say the latter.
CORRECT ANSWER:
a- Cell-surface receptors bind polar signaling molecules; intracellular receptors bind nonpolar signaling molecules.
STEP-BY-STEP EXPLANATION:
The complete question from book is
According to Figure 9.6, what is a key difference between cell signaling by a cell-surface receptor and cell signaling by an intracellular receptor?
a- Cell-surface receptors bind polar signaling molecules; intracellular receptors bind nonpolar signaling molecules.
b- Signaling molecules that bind to cell-surface receptors lead to cellular responses restricted to the cytoplasm; signaling molecules that bind to intracellular receptors lead to cellular responses restricted to the nucleus.
c- Cell-surface receptors bind to specific signaling molecules; intracellular receptors bind any signaling molecule.
d- Cell-surface receptors typically bind to signaling molecules that are smaller than those bound by intracellular receptors.
e- None of the other answer options is correct.
<span>Reactants
Hope this helps.</span>