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What did Griffith’s experiment demonstrate about DNA?

It provided evidence that DNA is the genetic material.

What was the key finding in the Hershey-Chase experiment?

It showed that DNA, not protein, is responsible for carrying genetic information.

What is the structure of DNA nucleotides composed of?

A phosphate group, a deoxyribose sugar, and a nitrogenous base.

What is the three-dimensional structure of DNA?

It is a double helix.

What did the Meselson and Stahl experiment determine about DNA replication?

It demonstrated that DNA replication is semiconservative.

What is the origin of replication?

The specific location where DNA replication begins.

What is a replication bubble?

A region where the DNA strands have separated to allow replication.

What is a replication fork?

The area where the DNA is being unwound for replication.

What enzyme is responsible for unwinding the DNA helix during replication?

Helicase.

What is the function of single-strand binding proteins?

To stabilize unwound DNA strands and prevent them from re-annealing.

What is the role of topoisomerase in DNA replication?

To relieve the tension in the DNA helix that builds up ahead of the replication fork.

What does primase do?

Synthesizes the RNA primer needed for DNA polymerase to start replication.

What is the function of DNA polymerase III?

It synthesizes new DNA strands by adding nucleotides to the growing chain.

What does DNA polymerase I do during replication?

It removes RNA primers and replaces them with DNA nucleotides.

What is the role of DNA ligase?

To join Okazaki fragments on the lagging strand together.

What are the differences between leading strand and lagging strand synthesis?

Leading strand is synthesized continuously, while lagging strand is synthesized in short fragments.

What are telomeres?

The protective ends of linear chromosomes that prevent degradation.

What is telomerase?

An enzyme that extends the telomeres of chromosomes.

What is a nucleoid?

The region in a prokaryotic cell where the DNA is located.

What is chromatin?

The complex of DNA and proteins that forms chromosomes within the nucleus.

What are histone proteins?

Proteins that help package DNA into a compact, organized form.

What is a nucleosome?

A structural unit of a eukaryotic chromosome, consisting of DNA wrapped around histone proteins.

What is the difference between euchromatin and heterochromatin?

Euchromatin is less condensed and actively transcribed, whereas heterochromatin is more condensed and generally not transcribed.