Over the past 60 years, the level of carbon dioxide in the atmosphere has been continually increasing. many scientists hypothesize that this increase has led to an imbalance in the carbon cycle and a climatic trend known as global warming.

In familial hypercholesterolemia individuals homozygous for the allele causing the disorder completely lack receptors on liver cells that take up cholesterol from the blood stream. heterozygous have one-half the number of receptors while individuals homozygous for the normal allele are phenotypically normal. this is an example of a. epistasis b. complete dominance c. incomplete dominance d. codominance

When coal has reached it hardest, darkest form, it is called select one: 0 a. sub-bituminous b. lignite c. bituminous d. antrhacite next page

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.