Which of the following is a model that shows the amount of energy available as it
flows through an ecosystem?
A) niche
B) energy pyramid
C) carrying capacity
D) food chain

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Compare and contrast cladistics and phylogeny. what are their advantages and disadvantages? which is the most useful in understanding how an organism developed into its current form? which concept most strongly supports your opinion about the origin of any given organism?

Apatient has an open displaced fracture of the second cervical vertebra. this is her fifth visit and the fracture is healing normally. what icd-10-cm code is reported?