All Free Biology MCQs with Answers

• A. Fishelsoni
• B. Thermus aquaticus
• C. E. Coli
• D. Both Fishelsoni and Thermus aquaticus

Explanation: Thermus aquaticus is a bacterium that lives in hot springs, and hydrothermal vents, and Tqa polymerase was identified as an enzyme able to withstand the protein-denaturing conditions like high temperature required during PCR. Therefore is the source of the DNA polymerase used in the PCR technique.

• A. PCR
• B. Tissue Culture
• C. Micropropagation
• D. Macropropagation

Explanation: Micropropagation is the artificial process of producing plants vegetatively through tissue culture or cell culture techniques. In this artificial process of propagation, plants are produced in vitro by asexual means of reproduction or by vegetative propagation.

• A. PCR
• B. PBr 103
• C. Eco R1
• D. Reverse transcriptase

Explanation: The general role of reverse transcriptase is to convert RNA sequences to cDNA sequences that are capable of inserting into different areas of the genome.

• A. BAC
• B. YAC
• C. Cosmids
• D. EcoRI

Explanation: Cloning: It is a technique for developing a large number of genes, identical cells, tissues, or organisms. Vector: Vectors are required to make rDNA molecules for gene cloning. EcorI does not act as a cloning vector. As it is a restriction enzyme, which cut double-stranded DNA into single-stranded complementary strands.

• A. 2 different sources
• B. Single source
• C. 2 same sources
• D. 3 same sources

Explanation: Recombinant DNA technology is the joining together of DNA molecules from two different species. The recombinant DNA molecule is inserted into a host organism to produce new genetic combinations that are of value to science, medicine, agriculture, and industry.

• A. Techniques used for the identification of fingerprints of individuals
• B. Molecular analysis of profiles of DNA samples
• C. Analysis of DNA samples using imprinting devices
• D. Both Techniques are used for the identification of fingerprints of individuals and Analysis of DNA samples using imprinting devices

Explanation: DNA fingerprinting is also called DNA typing, DNA profiling in genetics, it is the method in which a small amount of DNA material is isolated, and the variables of elements of DNA are identified. DNA fingerprinting refers to the molecular analysis of the profile of DNA samples. Short nucleotide repeats are important for DNA fingerprinting which vary in number from person to person but are inherited.

• A. Small size vector
• B. Large size vector
• C. Large size vector with no origin of replication.
• D. Small size vector with no origin of replication.

Explanation: In molecular cloning, a vector is a DNA molecule used as a vehicle to artificially carry foreign genetic material into another cell, where it can be replicated and/or expressed. A vector containing foreign DNA is termed recombinant DNA. A small size is the suitable vector to be incorporated with the large external DNA fragment because it should be small in size so that it can easily integrate into the host cell. It should be capable of inserting a large segment of DNA. It should possess multiple cloning sites.

• A. Primer
• B. Probe
• C. Restriction enzyme
• D. Taq Polymerase

Explanation: Aprobe is a single-stranded sequence of DNA or RNA used to search for its complementary sequence in a sample genome. DNA probes are important tools in diagnostics to ensure high specificity and sensitivity. They are used in molecular biology methods like PCR. Fluorescence in situ hybridization (FISH) is a laboratory technique for detecting and locating a specific DNA sequence on a chromosome. The technique relies on exposing chromosomes to a small DNA sequence called a probe that has a fluorescent molecule attached to it.

• A. Agarose
• B. Charge in DNA
• C. Fluorescent dye
• D. Radioactive dye

Explanation: Fluorescent dyes, also known as reactive dyes or fluorophores are used for locating dna bands. Fluorescence is used in biology as a non-destructive way of analysing biological molecules, even at low concentrations, by means of the molecule's intrinsic fluorescence, or by attaching it with a fluorophore therefore dna bands can easily be seen.

• A. Ligation
• B. No ligation
• C. Tight ligation
• D. Cloning

Explanation: The DNA ligase catalyzes the formation of covalent phosphodiester linkages, which permanently join the nucleotides together. After ligation, the insert DNA is physically attached to the backbone and the complete plasmid can be transformed into bacterial cells for propagation so if vector is cut by different restrict]tion enzyme ligation occurs.