Exploring DNA Structure and Replication

This video is part of the IB Biology series, focusing on nucleic acids. It covers the structure of DNA and RNA, highlighting the contributions of Franklin, Wilkins, Watson, and Crick. The Hershey-Chase experiment is discussed, proving DNA as the genetic material. The video also explains DNA's organization at the molecular level and details the DNA replication process, including the roles of various enzymes and the concept of semi-conservative replication.

Who were the scientists that revealed the double helix structure of DNA?

• Franklin and Wilkins

• Mendel and Darwin

• Watson and Crick

• Hershey and Chase

What did the cross pattern observed by Franklin and Wilkins indicate?

• The presence of proteins

• The size of DNA

• The presence of RNA

• A helical shape

What was the main conclusion of the Hershey-Chase experiment?

• Proteins make up genes

• Viruses do not contain genetic material

• RNA is the genetic material

• DNA makes up genes

Which nitrogenous bases are classified as purines?

• Adenine and Thymine

• Guanine and Cytosine

• Adenine and Guanine

• Thymine and Cytosine

What is the function of histones in eukaryotic DNA?

• To synthesize RNA

• To wrap and organize DNA

• To replicate DNA

• To break down DNA

What is the combined structure of DNA wrapped around histones called?

• Chromosome

• Nucleosome

• Ribosome

• Genome

Which enzyme unwinds the DNA during replication?

• DNA gyrase

• DNA polymerase

• DNA helicase

• DNA ligase

What is the role of DNA polymerase 3 in DNA replication?

• Adding nucleotides to the RNA primer

• Joining Okazaki fragments

• Replacing RNA primer with DNA

• Unwinding the DNA

What are the short strands of nitrogenous bases produced on the lagging strand called?

• Histones

• Nucleotides

• Okazaki fragments

• Leading strands

What does the term 'semi-conservative' mean in DNA replication?

• DNA replication does not require enzymes

• DNA replication occurs in one direction

• Each new DNA molecule has one old and one new strand

• Each new DNA molecule has two new strands