Pollution caused the environment to become more darkly colored, so moths were selected to be blacks and greys. Before pollution they were white and lighter colors. <span />
Answer: feed-back
When the product of a metabolic pathway accumulates, it may be able to slow down or turn off the pathway by inhibiting the activity of an enzyme that catalyzes an early step in the pathway. This is referred to as feed-back inhibition.
Explanation:
Feed-back inhibition is said to occur when the final product of a biochemical pathway signal the inactivation of the starting materials of the pathway.
For example: when pyruvate signal the inactivation of phosphofructokinase, the glycolytic pathway gets turned off.
The variety of all life forms on Earth.
The polarity of the water molecule helps it to cohere to nearby water molecules, forming a skin over it.
Answer:
D. Hypothesis.
Explanation:
A hypothesis is defined as an idea or explanation which can be further tested through study and experiments. It is a proposed explanation for a phenomenon.
Scientists generally base scientific hypotheses on previous observations that cannot be explained with the available scientific theories.