Complete the cycle for ice wedging.

1. water seeps into cracks.

3.ice widens the cracks

- repeat.

a. water evaporates.
b. water freezes.
c. the cracks close.
d. the rock breaks.

As a small change in a person's dna can cause a genetic disorder

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.

Describe characteristics of a good respitory surface