Bio Beyond: Genetic Replication
In the simulation below, build the strand that is complementary to
the one shown. In this case, you are not replicating the strand but
completing it. -Correct Answer ✔ ✔ Thymine
Adenine
Guanine
Cytosine
Cytosine
Thymine
Thymine
Adenine
Guanine
Thymine
What do the results Meselson and Stahl found for the first generation
mean? -Correct Answer ✔ ✔ All DNA used heavy and light
nitrogen and has the same mass
What do these results mean for the three proposed models? -Correct
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. -Correct
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? -Correct 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. -Correct Answer ✔ ✔ Leading
strand on second box
Okazaki fragment and lagging strand on last two boxes
Why are Okazaki fragments made on the lagging strand? -Correct
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? -
Correct Answer ✔ ✔ The fragments must be connected
In the simulation below, build the strand that is complementary to
the one shown. In this case, you are not replicating the strand but
completing it. -Correct Answer ✔ ✔ Thymine
Adenine
Guanine
Cytosine
Cytosine
Thymine
Thymine
Adenine
Guanine
Thymine
What do the results Meselson and Stahl found for the first generation
mean? -Correct Answer ✔ ✔ All DNA used heavy and light
nitrogen and has the same mass
What do these results mean for the three proposed models? -Correct
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. -Correct
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? -Correct 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. -Correct Answer ✔ ✔ Leading
strand on second box
Okazaki fragment and lagging strand on last two boxes
Why are Okazaki fragments made on the lagging strand? -Correct
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? -
Correct Answer ✔ ✔ The fragments must be connected
