Currently, two of the living elephant species (X and Y) are placed in the genus Loxodonta, and a third surviving species (Z) is placed in the genus Elephas.    Assuming this classification reflects evolutionary relatedness, which of the following is the most accurate evolutionary tree?    

What is the primary chemical factor that stimulates breathing?

What is the role of erythropoietin produced by the kidneys?

  The following graph shows the size of a plant population in a forest. The population was recently affected by a wildfire, as indicated in the graph. Which of the following statements is most likely true about the plant population immediately after the wildfire?

What is the primary function of the alveoli in the lungs?

Which ion is most important for water reabsorption in the kidneys?

What is the role of the villi in the small intestine?

  Which one of the following conditions would most likely cause allele frequencies of a gene pool to change by chance (hint: by imperfect sampling or sampling error!!!)?  

  Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles in their communities.   

What is the triangular region at the base of the urinary bladder called?