Which of the Following Would Most Likely Lead to the Development

question 102

Multiple Choice

Which of the following would most likely lead to the development of two heads in a Drosophila embryo, one at each end?

• A) Injecting Nanos protein into the posterior region of the egg
• B) Knocking out the expression of the bicoid gene in the anterior region of the egg
• C) Knocking out the expression of the bicoid gene in the posterior region of the egg
• D) Injecting the posterior region of the egg with cytoplasm from the anterior region of another wild-type egg.
• E) injecting the anterior region of the egg with cytoplasm from the posterior region of another wild-type egg.

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Definitions:

External Validity

The extent to which the results of a study can be generalized to other situations and to other people outside of the experimental setting.

Internal Validity

The extent to which a study can demonstrate that a causal relationship exists between two variables, free from the influence of extraneous variables.

Single-Case Experimental Designs

Research methods that focus on obtaining detailed information from individual participants to assess the impacts of interventions.

Interventions

Actions or processes of intervening, designed to improve health or alter the course of a disease, typically referring to treatments, therapies, or programs.