Answer:
D. Solar energy is a renewable resource.
Explanation:
Solar power is energy from the sun that is converted into thermal or electrical energy. Solar energy is the cleanest and most abundant renewable energy source available, and the U.S. has some of the richest solar resources in the world.
Answer:
b. to amplify the signal
Explanation:
A multi-enzyme phosphorylation cascade is a series of signaling events where one enzyme phosphorylates to another, then this last enzyme acts to phosphorylate another protein and so successively, thereby triggering a chain reaction that leads to the phosphorylation of hundreds or even thousands of proteins. A multi-enzyme phosphorylation cascade is known to increase the number of activated (phosphorylated) proteins at each step of the signaling cascade. Phosphorylation is a posttranslational modification capable of activating proteins during long periods, thereby a phosphorylation cascade also enables the activation of multiple proteins before these proteins become inactive again.
Vertebrates and invertebrates
"The half of the Moon that points toward the Sun looks bright because it is lit by sunlight. The Moon appears to change shape because we see different amounts of the lit part as the Moon orbits Earth. ... As it moves around Earth, more and more of the lit side comes into view."
