Grains Represent Radioactive Material Within the Replicating Eye

question 25

Multiple Choice

Grains represent radioactive material within the replicating eye.
-In an experiment, DNA is allowed to replicate in an environment with all necessary enzymes, dATP, dCTP, dGTP, and radioactively labeled dTTP (³H thymidine) for several minutes and then switched to nonradioactive medium. It is then viewed by electron microscopy and autoradiography. The figure above represents the results.
Which of the following is the most likely interpretation?

• A) There are two replication forks going in opposite directions.
• B) Thymidine is only being added where the DNA strands are furthest apart.
• C) Thymidine is only added at the very beginning of replication.
• D) Replication proceeds in one direction only.

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Definitions:

Circadian Arousal

The fluctuation of physiological and behavioral processes, including wakefulness and sleepiness, following a roughly 24-hour cycle, influenced by external light-dark cycles.

Melatonin Secretion

The release of the hormone melatonin by the pineal gland, typically increased in response to darkness, influencing sleep patterns.

Sharpest Thinking

The state of having the most acute, focused, or keen cognitive function, allowing for optimal problem-solving and decision-making.

Sequential Processing

The method of processing information in a linear, step-by-step manner, often contrasted with parallel processing.