Prepare for NEET Biology Molecular Basis of Inheritance with MCQs & PYQs on NEET.GUIDE. Access free practice, previous year questions, and expert explanations of DNA replication and genetics.
The Hershey-Chase experiment utilized radioactive isotopes to label different components of bacteriophages. Which of the following combinations accurately reflects the isotopes used and the components they labeled?
32P for protein and 35S for DNA
35S for both DNA and protein
32P for DNA and 35S for protein
32P for both DNA and protein
In the Hershey-Chase experiment, what crucial observation confirmed that DNA, and not protein, was the genetic material injected into bacteria by bacteriophages?
Radioactive sulfur (35S) was found inside the bacterial cells, while radioactive phosphorus (32P) remained outside.
Both radioactive phosphorus (32P) and sulfur (35S) were found inside the bacterial cells.
Neither radioactive phosphorus (32P) nor sulfur (35S) were found inside the bacterial cells.
Radioactive phosphorus (32P) was found inside the bacterial cells, while radioactive sulfur (35S) remained outside.
Eukaryotic DNA replication is a complex process involving multiple proteins. Which of the following is NOT a function of Replication Protein A (RPA)?
Stabilizing single-stranded DNA
Preventing reannealing of separated DNA strands
Facilitating the binding of other replication proteins
Catalyzing the formation of phosphodiester bonds
Which statement BEST describes the difference between rho-dependent and rho-independent transcription termination in prokaryotes?
Rho-dependent termination requires a helicase activity, while rho-independent termination relies on a hairpin structure and a poly-U sequence.
Rho-dependent termination occurs only in the presence of specific antibiotics, while rho-independent termination is the normal mechanism.
Rho-dependent termination utilizes sigma factor, while rho-independent termination utilizes rho factor.
Rho-dependent termination involves the formation of a G-quadruplex structure, while rho-independent termination involves a stem-loop structure.
One of the surprising findings of the Human Genome Project was:
The high percentage of repetitive DNA sequences
The existence of non-coding RNA molecules
The relatively low number of protein-coding genes
The presence of mitochondrial DNA
A mutant strain of E. coli is found where the repressor protein of the lac operon has lost its ability to bind to allolactose. In the presence of lactose, what would be the expected expression level of the lac operon genes in this mutant compared to a wild-type strain?
Higher than wild-type
Lower than wild-type
The same as wild-type
Completely absent
What radioactive element was used to label the protein part of the bacteriophage in the Hershey-Chase experiment?
Sulfur (35S)
Phosphorus (32P)
Nitrogen (15N)
Carbon (14C)
Which of the following is NOT a key feature of the transforming principle, as demonstrated by Griffith?
It is composed of protein.
It can change the characteristics of bacteria.
It can be passed from one generation of bacteria to the next.
It was later identified as DNA.
What is the function of single-strand binding proteins (SSBPs) in DNA replication?
Initiate DNA synthesis
Unwind the DNA double helix
Prevent reannealing of separated DNA strands
Join Okazaki fragments
A frameshift mutation occurs in a gene encoding a crucial enzyme. Which of the following is the LEAST likely consequence?
A silent mutation resulting in no change to the enzyme's function.
A truncated, non-functional protein due to a premature stop codon.
An altered amino acid sequence leading to a change in enzyme activity.
A protein with a completely different amino acid sequence and function.
