What is a phylum is made up of many different A. orders

B. families

C. classes

thinking it would be physical characteristics

the answer is b.) hydrogen bonds between bases.

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: