This cycle and the oxygen cycle both include photosynthesis and respiration

in the year 2850, humans successfully colonized mars. the martian modules that were constructed could hold only a small population of people. it is now a century later, and the population on mars has grown to 600 people. of the current mars population, 45 people express the recessive phenotype for phenylketon- uria (pku) syndrome (pp genotype).

explanation:

colors do exist. the color of the sky is actually violet; humans percieve the color of the sky as blue.

a bird that nests only in a particular tree species.