Hershey-Chase Experiment: DNA as Genetic Material

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What is the primary purpose of using bacteriophage T-2 in the experiments?

To determine the hereditary molecule (correct)
To examine the function of proteins
To study the structure of DNA
To understand the central dogma

What is the result of centrifugation in the experiment?

Pellet formation with radiolabel (correct)
Separation of DNA and protein
Supernatant formation with radiolabel
Mixing of DNA and protein

What is the central dogma?

The pathway from protein to RNA to DNA
The pathway from DNA to protein to RNA
The pathway from RNA to DNA to protein
The pathway from DNA to RNA to protein (correct)

What is the purpose of transcription in gene expression?

To yield a ribonucleic acid copy of specific genes (A) Signup and view all the answers

What is the product of replication?

DNA (C) Signup and view all the answers

What is the composition of a nucleotide?

Sugar, phosphate, and nitrogenous base (B) Signup and view all the answers

What is the difference between a nucleoside and a nucleotide?

A nucleoside has a sugar and a base, while a nucleotide has a sugar, base, and phosphate (B) Signup and view all the answers

What is the shape of the DNA molecule?

A double helix (B) Signup and view all the answers

What is the function of messenger RNA (mRNA) in translation?

To carry genetic information from DNA to the ribosome (C) Signup and view all the answers

What is the result of DNA replication?

The creation of an identical DNA molecule (C) Signup and view all the answers

What is the role of DnaC in the initiation of DNA replication?

To load helicase in the form of DNA B and bring it to the origin of replication (A) Signup and view all the answers

What is the outcome of the binding of DnaA protein to the DNAa box?

A conformational change in the DNA strand, causing it to bend (B) Signup and view all the answers

What is the purpose of single-stranded DNA binding proteins in DNA replication?

To hold the unwound DNA strands apart (B) Signup and view all the answers

What is the function of DnaG in DNA replication?

To lay down the initial RNA primers (D) Signup and view all the answers

What is the result of the activity of DNA polymerase 3 during elongation?

The synthesis of a continuous leading strand and a discontinuous lagging strand (C) Signup and view all the answers

What is the characteristic of the lagging strand during DNA replication?

It is synthesized discontinuously in the 5' to 3' direction (D) Signup and view all the answers

What is the role of the Shine-Dalgarno sequence in mRNA?

To align the ribosome machinery to the correct starting location (B) Signup and view all the answers

What is the function of initiation factors in bacteria?

To help form the initiation complex (C) Signup and view all the answers

What is the difference between the initiator tRNA in bacteria and archaea/eukaryotes?

Bacteria use N-formylmethionine-tRNA, while archaea/eukaryotes use methionine-tRNA (A) Signup and view all the answers

When does the initiation of translation begin in bacteria?

When the initiator codon binds to the 16S rRNA (A) Signup and view all the answers

What is the purpose of the formyl group added to the amino side of methionine in bacteria?

To block the addition of other amino acids to the carboxy terminus (B) Signup and view all the answers

Why is the initiation complex formed only when there is mRNA in the environment that needs to be translated?

To prevent energy waste (C) Signup and view all the answers

What feature of bacteria makes them ideal for genetic manipulation?

Simple genome (B) Signup and view all the answers

What is the purpose of using auxotrophs in genetic experiments?

To observe genetic manipulations (A) Signup and view all the answers

What is the advantage of using bacteria in genetic experiments compared to eukaryotic organisms?

Bacteria have a simpler genome and grow quickly (C) Signup and view all the answers

What is the purpose of screening in genetic experiments?

To look for changes in phenotype (D) Signup and view all the answers

What is the purpose of using a selective medium in genetic experiments?

To inhibit the growth of microbes lacking the desired gene (A) Signup and view all the answers

What is the purpose of blue-white screening in genetic experiments?

To insert a gene of interest and block a particular pathway (B) Signup and view all the answers

What is the primary function of transposase in mobile genetic elements?

To recognize and cut specific DNA sequences during transposition (C) Signup and view all the answers

What is the characteristic of a simple transposon?

It contains only the gene for the enzyme transposase with inverted repeats (D) Signup and view all the answers

What is the result of a transposon inserting into a gene?

The gene is mutated, and its function may be altered (A) Signup and view all the answers

What is the role of resolvase in replicative transposition?

It resolves the cointegrate structure formed during replicative transposition (D) Signup and view all the answers

What is the term for the process by which transposons move from one location to another in the genome?

Transposition (B) Signup and view all the answers

What is the characteristic of a replicative transposon?

It makes a copy of itself in the genome during transposition (A) Signup and view all the answers

What is the role of inverted repeats in transposons?

They serve as recognition sites for transposase (A) Signup and view all the answers

What is the effect of a transposon carrying a promoter or activator?

It turns on nearby genes (D) Signup and view all the answers

What is the role of transposons in plasmid evolution?

They are involved in the transfer of antibiotic resistance genes between plasmids (A) Signup and view all the answers

What is the term for the process by which F factors integrate into the host chromosome?

Integration (C) Signup and view all the answers