Paleontologists can identify organisms that may be ancient relatives of those living today. By looking at fossils they can also suggest how these organisms lived together in an ancient habitat. Few organisms become fossilized because the circumstances that an organism has to be in is very specific.
Earth's mantle plays an important role in the evolution of the crust and provides the thermal and mechanical driving forces for plate tectonics. Heat liberated by the core is transferred into the mantle where most of it (> 90%) is convected through the mantle to the base of the lithosphere.
Pupillary response is a physiological response that varies the size of the pupil, via the optic and oculomotor cranial nerve. Involuntary reflex reaction to exposure or inexposure to light—in low light conditions a dilated pupil lets more light into the eye. :)
Answer:
Some mutagens strip DNA nucleotides (bases) of essential modifications—for example, they deaminate the bases—such that these bases resemble different nucleotides and confuse the DNA replication machinery. Subsequent rounds of DNA replication then permanently incorporate such changes.
Explanation:
