The Images Above Are of DNA at Various Levels of Coiling

question 55

Multiple Choice

The images above are of DNA at various levels of coiling and folding. Use this image to answer the questions below.
-For a science fair project, two students decided to repeat the Hershey and Chase experiment, with modifications. They decided to label the nitrogen of the DNA, rather than the phosphate. They reasoned that each nucleotide has only one phosphate and two to five nitrogens. Thus, labelling the nitrogens would provide a stronger signal than labelling the phosphates. Why won't this experiment work?

• A)There is no radioactive isotope of nitrogen.
• B)Radioactive nitrogen has a half-life of 100 000 years, and the material would be too dangerous for too long.
• C)Avery et al. have already concluded that this experiment showed inconclusive results.
• D)Although there are more nitrogens in a nucleotide, labelled phosphates actually have 16 extra neutrons; therefore, they are more radioactive.
• E)Amino acids (and thus proteins)also have nitrogen atoms; thus, the radioactivity would not distinguish between DNA and proteins.

Define and understand network composition and overlap, and their influence on relationship outcomes.

Develop strategies for counseling couples experiencing external stressors.

Propose initiatives to strengthen marriages among low-income families by addressing external stress factors.

Understand the basics of DNA structure and function, including the role of genes and the concept of base pairing.

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Definitions:

Control

The power to influence or direct people's behavior or the course of events.

Third Variables

Factors that are not directly under study but may influence the relationship between the variables being examined in research.

Learned Helplessness

A condition in which a person suffers from a sense of powerlessness, arising from a traumatic event or persistent failure to succeed.

Psychological Symptoms

Manifestations of mental or emotional distress, which can include mood swings, anxiety, depression, or abnormal behavior.