Activation energy is the amount of energy required to begin a chemical reaction.
The alveoli are lined with mucus and are surrounded by a network of blood capillaries. They have very thin walls for gases to be absorbed through. An individual air sac is called an alveolus. The layer of moisture in the alveoli allows gases to dissolve so that they can diffuse quickly.
The most vocal reptile ARE THE CROCODILES.
Crocodiles use different types of calls, smells and water behavior to communicate with one another. Scientists have discovered that some species of crocodiles can pass across up to twenty messages using sound alone. The sounds made can be used to signify threat, distress or it can be used to attract others for courtship purpose. Crocodiles also communicate through smells and through water behaviors.
The answer is; B
Mutation is one source of variation (in addition to sex and gene flow). Mutations are rare and occur in a small proportion of individuals. However, due to the advantage that the genetic mutation confers to these individuals, their chances of passing the genes to the next generation is higher than that of the general population.
This way, the allelic frequencies of these advantageous mutated genes increase with each generation and eventually become the majority population over time.
I think it changes the physical appearance of that certain trait. For example, eye color. If the proteins are set up a certain way for brown eyes, then changed, there would be blue eyes.