B) How many species has the genus Homo had in the course of history and when did this
genus first arise? (2 points)

The genus Homo had three species, H. habilis, H. rudolfensis, and H. erectus, and the genus first arose about 2.5 million years ago

Explanation:

label a cell membrane

label b cytoplasm

label c ribosomes

label d dna

the membrane forms the outside of the cell

cytoplasm is the liquid within

ribosomes are the components within that distribute rna

the dna is the genetic make-up

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: