Question
10. A scientist uses radioactive isotopes to label a double-stranded molecule of DNA. Then the DNA undergoes replication in a non-radioactive medium. Where are the two original radioactive strands of DNA?
* 2 points
a. Both strands are destroyed due to instability, and both are part of the same molecule of DNA.
b. Both strands are intact, and both are part of the same molecule of DNA.
c. One strand is intact, and the other strand is broken apart and distributed among the new DNA molecules.
d. Both strands are intact broken apart, and their pieces are distributed among the new DNA molecules.
* 2 points
a. Both strands are destroyed due to instability, and both are part of the same molecule of DNA.
b. Both strands are intact, and both are part of the same molecule of DNA.
c. One strand is intact, and the other strand is broken apart and distributed among the new DNA molecules.
d. Both strands are intact broken apart, and their pieces are distributed among the new DNA molecules.
Answers
GPT-4o mini
In the scenario described, the scientist uses radioactive isotopes to label a double-stranded DNA molecule, which then undergoes replication in a non-radioactive medium. During DNA replication, each original strand serves as a template for the synthesis of a new complementary strand. Therefore, the two original radioactive strands will remain intact and will each be part of the two newly formed double-stranded DNA molecules.
The correct answer is:
**b. Both strands are intact, and both are part of the same molecule of DNA.**
This is because during replication, the two strands of the original DNA molecule separate, allowing each strand to serve as a template for the synthesis of a new complementary strand, resulting in two double-stranded DNA molecules after replication. Each of the new molecules consists of one original radioactive strand and one newly synthesized non-radioactive strand.
The correct answer is:
**b. Both strands are intact, and both are part of the same molecule of DNA.**
This is because during replication, the two strands of the original DNA molecule separate, allowing each strand to serve as a template for the synthesis of a new complementary strand, resulting in two double-stranded DNA molecules after replication. Each of the new molecules consists of one original radioactive strand and one newly synthesized non-radioactive strand.