Replication of DNA

What significant discovery did British scientists James Watson and Francis Crick announce in 1953?

• Discovery of penicillin

• Discovery of the double helix structure of DNA

• Identification of the periodic table

• Invention of the internet

Answer explanation

Watson and Crick announced the discovery of the double helix structure of DNA in 1953.

What are the components of a DNA molecule?

• Phosphate group, sugar molecule (deoxyribose), and nitrogenous base (adenine, thymine, cytosine, or guanine)

• Phosphate group, sugar molecule (ribose), and nitrogenous base (adenine, thymine, cytosine, or guanine)

• Hydrogen group, sugar molecule (deoxyribose), and nitrogenous base (adenine, thymine, cytosine, or guanine)

• Phosphate group, sugar molecule (deoxyribose), and nitrogenous base (uracil, thymine, cytosine, or guanine)

Answer explanation

The components of a DNA molecule are a phosphate group, sugar molecule (deoxyribose), and nitrogenous base (adenine, thymine, cytosine, or guanine). This choice is correct as it accurately lists all the components of DNA.

Describe the role of DNA helicase, DNA polymerase, and DNA ligase.

• DNA helicase synthesizes new DNA strands

• DNA helicase unwinds DNA, DNA polymerase synthesizes new DNA strands, and DNA ligase seals the nicks in the DNA backbone.

• DNA polymerase unwinds DNA

• DNA ligase unwinds DNA

Answer explanation

DNA helicase unwinds DNA, DNA polymerase synthesizes new DNA strands, and DNA ligase seals the nicks in the DNA backbone.

What is the initial step in the process of synthesizing a new strand of DNA?

• Separation of the two DNA strands

• Addition of nucleotides to the template strand

• Binding of RNA primers to the DNA template

• Formation of phosphodiester bonds between nucleotides

Answer explanation

The initial step in the process of synthesizing a new strand of DNA is the separation of the two DNA strands.

Explain the process of DNA replication in your own words.

• DNA replication occurs only in prokaryotic cells.

• DNA replication is the process by which a cell makes an identical copy of its DNA.

• DNA replication involves the synthesis of new proteins.

• DNA replication is the process of creating RNA molecules.

Answer explanation

DNA replication is the process by which a cell makes an identical copy of its DNA.

Arrange the following steps in the correct order for protein synthesis:

• Protein Folding, Translation, mRNA Processing, Transcription

• Translation, mRNA Processing, Transcription, Protein Folding

• Transcription, mRNA Processing, Translation, Protein Folding

• Transcription, Protein Folding, mRNA Processing, Translation

Answer explanation

The correct order for protein synthesis is Transcription, mRNA Processing, Translation, Protein Folding.

Discuss the differences in DNA replication between eukaryotes and prokaryotes.

• Eukaryotes replicate DNA in the cytoplasm with multiple origins, while prokaryotes replicate DNA in the nucleus with a single origin.

• Eukaryotes replicate DNA in the nucleus with multiple origins, while prokaryotes replicate DNA in the cytoplasm with a single origin.

• Both eukaryotes and prokaryotes replicate DNA in the nucleus with multiple origins.

• Eukaryotes replicate DNA in the cytoplasm with a single origin, while prokaryotes replicate DNA in the nucleus with multiple origins.

Answer explanation

Eukaryotes replicate DNA in the nucleus with multiple origins, while prokaryotes replicate DNA in the cytoplasm with a single origin. This choice correctly highlights the key differences in DNA replication between eukaryotes and prokaryotes.

Classify each statement as eukaryotic transcription or prokaryotic transcription.

• Prokaryotic translation

• Eukaryotic transcription

• Eukaryotic translation

• Prokaryotic replication

Answer explanation

The correct choice is Eukaryotic transcription because it involves the process of transcribing DNA into mRNA in eukaryotic cells.

Discuss the process of DNA replication, focusing on the role of Okazaki fragments in the lagging strand synthesis.

• Okazaki fragments are responsible for leading strand synthesis

• Okazaki fragments are only found in prokaryotic cells

• Okazaki fragments play a crucial role in lagging strand synthesis by allowing for the discontinuous replication of DNA.

• Okazaki fragments are involved in the repair of damaged DNA

Answer explanation

Okazaki fragments play a crucial role in lagging strand synthesis by allowing for the discontinuous replication of DNA.

What would be the sequence of the template strand if the nontemplate strand has the sequence: 5' TATCGGGAATTC 3' 3'

• 3' TATCGGGAATTC 3'

• 3' ATAGCCCTTAAG 5'

• 5' ATAGCCCTTAAG 3'

• 3' TATCGGGAATTC 5'

Answer explanation

The template strand is complementary to the nontemplate strand. Therefore, the sequence of the template strand would be 3' ATAGCCCTTAAG 5', matching the nontemplate strand sequence.