BIO BEYOND GENETIC REPLICATION
REVIEW 2026 UPDATED QUESTIONS
VERIFIED ANSWERS COMPLETE GUIDE
◉ Is the DNA of the first generation grown in the presence of light
nitrogen heavier or lighter than the original generation's DNA?
Answer: Lighter
◉ What do the results Meselson and Stahl found for the first
generation mean?
Answer: All DNA used heavy and light nitrogen and has the same
mass
◉ What do these results mean for the three proposed models?
Answer: The semi-conservative model is supported
◉ Now that you've learned about how new and old DNA strands are
matched during replication, you're ready to dive deeper into exactly
how DNA replicates. After unwinding and breaking the bonds
holding the two strands of DNA together, replication can begin.
Answer: <---
Fork
, --->
◉ However, DNA replication presented an interesting problem that
wasn't solved until 1966: DNA is opened in one direction and DNA
polymerases only work in one direction, but the two strands of DNA
run in opposite directions (they are antiparallel).
Why is this an issue?
Answer: One DNA polymerase has to run away from the fork
◉ The strand where DNA polymerase moves away from the fork is
called the lagging strand and is made in little pieces called Okazaki
fragments, named after their discoverer, Reiji Okazaki.
To continue, label the leading strand, lagging strand, and an Okazaki
fragment in the image to the right.
Answer: Leading strand on second box
Okazaki fragment and lagging strand on last two boxes
◉ Why are Okazaki fragments made on the lagging strand?
Answer: DNA polymerase has to copy away from the fork and jump
back to copy more when the fork moves
◉ What has to happen to the Okazaki fragments after they are
made?
REVIEW 2026 UPDATED QUESTIONS
VERIFIED ANSWERS COMPLETE GUIDE
◉ Is the DNA of the first generation grown in the presence of light
nitrogen heavier or lighter than the original generation's DNA?
Answer: Lighter
◉ What do the results Meselson and Stahl found for the first
generation mean?
Answer: All DNA used heavy and light nitrogen and has the same
mass
◉ What do these results mean for the three proposed models?
Answer: The semi-conservative model is supported
◉ Now that you've learned about how new and old DNA strands are
matched during replication, you're ready to dive deeper into exactly
how DNA replicates. After unwinding and breaking the bonds
holding the two strands of DNA together, replication can begin.
Answer: <---
Fork
, --->
◉ However, DNA replication presented an interesting problem that
wasn't solved until 1966: DNA is opened in one direction and DNA
polymerases only work in one direction, but the two strands of DNA
run in opposite directions (they are antiparallel).
Why is this an issue?
Answer: One DNA polymerase has to run away from the fork
◉ The strand where DNA polymerase moves away from the fork is
called the lagging strand and is made in little pieces called Okazaki
fragments, named after their discoverer, Reiji Okazaki.
To continue, label the leading strand, lagging strand, and an Okazaki
fragment in the image to the right.
Answer: Leading strand on second box
Okazaki fragment and lagging strand on last two boxes
◉ Why are Okazaki fragments made on the lagging strand?
Answer: DNA polymerase has to copy away from the fork and jump
back to copy more when the fork moves
◉ What has to happen to the Okazaki fragments after they are
made?
