What is a nonliving thing in an ecosystem a. Biotic Factor
b. Abiotic factor
c. Plant
d. Animal

Which best describes the digestive system of arthropods? a incomplete, two openings b complete, one opening c two-way, one opening d one-way, two openings

In which terrestrial biome can you find trees that produce cones instead of flowers and needles instead of leaves? have trees that produce cones instead of flowers and needles instead of leaves. the latitudes in this biome have evenly distributed precipitation throughout the year. is it high or low

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.