#Question id: 24641
#Unit 10. Ecological Principles
#Question id: 19879
#Unit 13. Methods in Biology
#Question id: 21124
#Unit 12. Applied Biology
#Question id: 8296
#Unit 9. Diversity of Life Forms
Giardia intestinalis can cause disease in several different mammalian species, including humans. Giardia organisms (G. intestinalis) that infect humans are similar morphologically to those that infect other mammals, thus they have been considered a single species. However, G. intestinalis has been divided into different subgroups based on their host and a few other characteristics. In 1999, a DNA sequence comparison study tested the hypothesis that these subgroups actually constitute different species. The following phylogenetic tree was constructed from the sequence comparison of rRNA from several subgroups of G. intestinalis and a few other morphologically distinct species of Giardia. The researchers concluded that the subgroups of Giardia are sufficiently different from one another genetically that they could be considered different species.
According to the phylogenetic tree in the figure above, G. intestinalis constitutes a ________ group.
#Question id: 968
#Unit 1. Molecules and their Interaction Relevant to Biology
In the urea cycle which molecule is transported from the mitochondrial matrix to the cytosol as ornithine is transported in the opposite direction?