Answer:
Every fossil tells us something about the age of the rock it's found in, and index fossils are the ones that tell us the most. Index fossils (also called key fossils or type fossils) are those that are used to define periods of geologic time
Explanation:
Pond organisms live in shallow water so they can produce
Answer:
exposure to ultraviolet radiation is a correct answer.
Explanation:
Ultraviolet light exposure results in the formation of pyrimidine dimers. Ultraviolet radiation damage the DNA by resulting in chemical changes.
Ultraviolet radiation is absorbed by the pyrimidine bases( cytosine and thymine in DNA) and result in the formation of covalent bonds between the succeeding bases.
The formation of the pyrimidine dimers results in the distortions of DNA helix and disrupt the base-pairing during the replication of DNA which results in a mutation.
