If You Start with 3 Double-Stranded DNA Fragments, After 4

question 32

Multiple Choice

If you start with 3 double-stranded DNA fragments, after 4 cycles of PCR you will have ______ fragments.

• A) 12
• B) 24
• C) 27
• D) 48
• E) 81

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Definitions:

Natural Experiments

Observational study designs where the researcher does not control the exposure but can study its effects due to external factors acting as an "experiment."

Internal Validity

The degree to which a study or experiment accurately demonstrates a causal relationship between the variables being tested, without the influence of external factors.

External Validity

The extent to which the findings of a study can be generalized to other settings, populations, or time periods.

Double-masked

A study design where neither the participants nor the experimenters know who is receiving a particular treatment, used to prevent bias.