TLS Online TPP Program

#Question id: 12908


Which statement is incorrect about CRISPR?

#SCPH28 | Zoology
  1. It  was first identified as an adaptive immunity pathway in prokaryotes providing resistance to bacteriophage and analogous to the RNA interference process found in eukaryotes. 
  2. It does not utilize double-stranded sequence-specific breaks and does not  repair using HDR via homologous recombination.
  3. The system consists of two parts, a short synthetic guide RNA ( gRNA) and a nonspecific double-stranded endonuclease termed Cas9. 
  4. It is also possible to program Cas9 with multiple guide RNAs to allow multiplex site-specific editing for designing large deletions, inversions and translocations.
More Questions
TLS Online TPP Program

#Question id: 8295

#SCPH28 | Zoology

Imagine that a phylogeny was developed for a group of mammals based on bone structure. Which of the following statements would be a reasonable prediction about a phylogeny for the same group of species based on similarities and differences in the structure of a particular enzyme?

TLS Online TPP Program

#Question id: 8296

#SCPH06 I Botany

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.

TLS Online TPP Program

#Question id: 8296

#SCPH28 | Zoology

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.

TLS Online TPP Program

#Question id: 8680

#SCPH06 I Botany

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


By examining the phylogenetic tree diagrammed in the figure above, what conclusion can you draw about the species G. microti?

TLS Online TPP Program

#Question id: 8680

#SCPH28 | Zoology

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


By examining the phylogenetic tree diagrammed in the figure above, what conclusion can you draw about the species G. microti?

TLS Online TPP Program

#Question id: 8682

#SCPH06 I Botany

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


Which of the following changes would a modern systematist be most likely to make after learning of the results of the rRNA analyses?