Figure 13.1 -For a Science Fair Project, Two Students Decided to Repeat

question 18

Multiple Choice

Figure 13.1
-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, labeling the nitrogens would provide a stronger signal than labeling the phosphates. Why won't this experiment work?

• A) There is no radioactive isotope of nitrogen.
• B) Avery et al. have already concluded that this experiment showed inconclusive results.
• C) Although there are more nitrogens in a nucleotide, labeled phosphates actually have 16 extra neutrons; therefore, they are more radioactive.
• D) Amino acids (and thus proteins) also have nitrogen atoms; thus, the radioactivity would not distinguish between DNA and proteins.

Understand advanced imaging techniques and their applications in diagnosing neurological disorders.

Comprehend the structure and function of the nervous system including differences between myelinated and unmyelinated nerve fibers.

Recognize and differentiate between various conditions and diseases affecting the nervous system based on symptoms and diagnostic tests.

Identify the role and significance of cerebrospinal fluid in neurological diagnostics.

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Definitions:

Secondary Learning

Learning that builds on previously acquired knowledge, skills, or understanding, often involving the application of basic concepts to new situations.

Learned Helplessness

A condition in which a person suffers from a sense of powerlessness, arising from a traumatic event or persistent failure to succeed, leading to the belief that one's actions have no effect on outcomes.

Aversive Stimulus

A stimulus that is unpleasant or painful, which an organism seeks to avoid or escape.

Positive Reinforcement

A technique used in behavioral psychology to increase the likelihood of a desired behavior by following it with the addition of a reinforcing stimulus.