You have been asked to share with a group of learners in a health course why it is important to
protect their skin from the sun's rays. While you
are explaining sunburns and the importance of
sunscreen, one of the group members asks, "If
the sun is so harmful, why does it not cause radi-
ation burns?"
You present the diagram below to answer the
question. Which layer should you point out dur-
ing your explanation?
A. Exosphere
B. Thermosphere
C. Ozone Layer
D. Troposphere

Building glycogen from glucose molecules is an example of what

How is ribosomal rna useful as a molecular clock? a. a large portion of the dna ring is not vital to structure or function, allowing it to accumulate neutral mutations. b. its rate of mutation increases over time as organisms continue to evolve and differentiate from each other. c. a slow mutation rate makes it useful for determining evolutionary relationships between ancient species. d. it is only found in select organisms, making it easier to compare relationships between species that have it.

Dna replication or repair occurs in a cell in all of thw following situations except when