Biology

DNA and Genetics

1,095 Questions

DNA and genetics questions explore molecular biology, DNA replication, and genetic engineering techniques. These topics are essential for various competitive exams requiring a strong foundation in life sciences. Practice these questions to understand complex biological processes thoroughly.

DNA replication mechanismsGenetic engineering techniquesGene editing toolsPolymerase chain reactionDNA sequencing methods

DNA and Genetics Questions

Multiple choice

Which of the following are consensus-based gene prediction programs?

  1. GenomeScan
  2. EST2Genome
  3. SGP-1
  4. GeneComber
  5. DIGIT

  1. 1, 2 and 3

  2. 2 and 4

  3. 3 and 4

  4. 3, 4 and 5

  5. 4 and 5
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Consensus-based gene prediction programs Because different prediction programs have different levels of sensitivity and specificity, it makes sense to combine results of multiple programs based on consensus. GeneComber is a web server that combines HMMgene and GenScan prediction results. DIGIT is another consensus-based web server. It uses prediction from three ab initio programs – FGENESH, GENSCAN, and HMMgene.

Multiple choice

Match the people in column I to their contribution toward the advancement of microbiology, in column II. Column I Column II P. Nathans, Smith, Arber 1. Reverse transcriptase Q. Dulbecco, Temin, Baltimore 2. Restriction enzymes R. Edelman and Porter 3. Bacterial photosynthesis pigments S. Deisenhofer, Huber, Michel 4. Antibodies

  1. P-1; Q-2; R-3; S-4

  2. P-1; Q-3; R-2; S-4

  3. P-2; Q-1; R-4; S-3

  4. P-3; Q-2; R-1; S-4

  5. P-3; Q-4; R-1; S-2
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Werner Arber, Dan Nathans and Hamilton Smith shared the 1978 Nobel Prize for the discovery of restriction enzymes and their application to problems of molecular genetics. Howard Martin Temin, Renato Dulbecco and David Baltimore shared the 1975 Nobel Prize for discovery of reverse transcriptase. Rodney Porter and Gerald Edelman won the Nobel Prize of 1972 for discovery of antibodies. Johann Deisenhofer, Robert Huber, and Hartmut Michel  shared 1988 Noble Prize for describing the structure of bacterial photosynthetic pigments.

Multiple choice

Match the columns: Column I Column II P. Richard J. Roberts and Phillip A. Sharp 1. Discovered that a gene can be separated onto different segments of DNA Q. Kary B. Mullis 2. Discovered the polymerase chain reaction to amplify DNA R. Peter C. Doherty and Rolf M. Zinkernagel 3. Discovered how cytotoxic T cells recognize virus-infected cells prior to destroying them S. Aaron Ciechanover, Avram Hershko, and Irwin Rose 4. Discovered how cells dispose of unwanted proteins in proteasomes.

  1. P-1; Q-2; R-3; S-4

  2. P-2; Q-1; R-4; S-3

  3. P-2; Q-3; R-4; S-1

  4. P-3; Q-2; R-4; S-1
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Roberts and Sharp discovered that a gene can be separated onto different segments of DNA. Kary B. Mullis discovered the polymerase chain reaction to amplify (make multiple copies of) DNA. Peter C. Doherty (Australia) and Rolf M. Zinkernagel (Switzerland) discovered how cytotoxic T cells recognize virus-infected cells prior to destroying them and were awarded Nobel Prize in 1996 for this work. Ciechanover, Hershko, and Rose discovered how cells dispose of unwanted proteins in proteasomes.

Multiple choice

Which of the following statements is FALSE?

  1. Restriction enzymes are used to cut DNA molecule.

  2. Restriction enzymes used in recombinant technology are Type II restriction enzymes.

  3. Restriction sites of type II enzymes are generally palindromic sequences.

  4. Type II restriction enzymes require Ca2+ as a cofactor ions for their activity.

  5. All
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Type II restriction enzymes usually require Mg2+ as a cofactor ions for their activity.

Multiple choice

Which the following is NOT correctly matched?

  1. MAtDB: a model organism database for Arabidopsis

  2. BLAST: A comprehensive database for the study of human genetics and molecular biology

  3. PROSITE: First secondary database developed

  4. Entrez: An information retrieval tool of NCBI GenBank

  5. DDBJ: A biological database that collects DNA sequences
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Basic Local Alignment Search Tool (BLAST) is an algorithm for comparing primary biological sequence information.

Multiple choice

Which of the following vectors is used for obtaining single stranded copies of cloned DNA?

  1. pUC7

  2. pSC101

  3. phage M13 vector

  4. phasmid vectors

  5. shuttle vectors
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

They are used for obtaining single stranded copies of cloned DNA, which are especially suited for DNA sequencing. They are derived from 6.4kb genome of E.coli filamentous bacteriophage M13. This phage has single-stranded DNA genome in phage particle that converts into double-stranded intermediate within host cell.

Multiple choice

What is the minimum genome size essential for packaging of the lambda vector into phage heads?

The lambda genome contains an origin of replication, genes for head and tail proteins and enzymes for DNA, lysis and lysogeny, and single-stranded protruding cohesive ends of 12 bases.The lambda genome remains linear in phage heads, but within E.coli cells the two cohesive ends join to form a circular molecule necessary for replication.

  1. 38kb

  2. 52kb

  3. 45kb

  4. 24kb

  5. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The lambda DNA must be larger than 38kb. The genes for lysogeny are located between 20 and 38kb, the whole or part of this segment is deleted to create lambda vectors to accommodate larger DNA inserts and to ensure that the recombinant phage is always lytic.

Multiple choice

What is the main objective of using Northern hybridization?

Northern hybridization involves the use of electrophoresis to separate RNA samples by size and detection with a hybridization probe complementary to part of or the entire target sequence. The term 'northern blot' actually refers specifically to the capillary transfer of RNA from the electrophoresis gel to the blotting membrane.

  1. To separate DNA

  2. To separate RNA

  3. To identify protein

  4. For DNA sequencing

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This technique is useful in the identification and separation of the RNA that is complementary to a specific DNA probe.

Multiple choice

In Western blotting, which of the following is used as probe for the identification of glycoproteins?

A hybridization probe is a fragment of DNA or RNA of variable length (usually 100-1000 bases long), which is used in DNA or RNA samples to detect the presence of nucleotide sequences (the DNA target) that are complementary to the sequence in the probe.

  1. Antibodies

  2. Molecular Beacon probes

  3. Cycling probe technology

  4. Lectins

  5. Locked Nucleic Acid probes
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A glycoprotein detected by lectin blotting with concanavalin A was also identified using this technique.

Multiple choice

The enzymatic procedure of DNA sequencing was developed by:

The enzymatic procedure or DNA sequencing: The DNA to be sequenced is used as a template for in vitro synthesis by DNA polymerase. Not only are all four normal deoxynucleotide triphosphates present within the reaction mixture (dATP, dTTP, dGTP, dCTP), but also present are dideoxynucleotides, one of each type (eg. ddATP) per sequencing reaction. Dideoxynucleotides are deoxynucleotides which lack hydroxyl groups at both the 2' and 3' positions, therefore cannot extend the chain by linking to another nucleotide. So,they act as chain terminators.

  1. Daniel Nathans

  2. Werner Arber

  3. Kary Mullis

  4. Brown

  5. F.Sanger
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

He developed the enzymatic procedure of DNA sequencing.