CUET LEVEL II BIOLOGY CHA-9 BIOTECHNOLGY;PRINCIPLES AND PROCESSS

The two core techniques that enabled the birth of modern biotechnology are _____

• red biotechnology and green biotechnology

• classical and traditional biotechnology

• genetics and mathematics

• genetic engineering and maintenance of a sterile environment

Answer explanation

Answer: d
Explanation: Genetic engineering and maintenance of a sterile environment are the two core techniques that gave birth to modern biotechnology. Genetic engineering uses techniques to alter the chemistry of genetic material and exploit them. While maintenance of a sterile environment enables the growth of only the desired organisms in large quantities for the manufacture of biotechnological products.

_____ is a product of biotechnology.

• Bacteria

• Skin

• Vaccine

• Plants

Answer explanation

Answer: c
Explanation: Vaccine is a product of biotechnology. The maintenance microbial contamination-free environment is necessary for chemical engineering processes. This environment enables the growth of the desired organism only. Thus, producing the organism in large quantities for the manufacture of biotechnological products like antibiotics, vaccines, enzymes, etc.

The techniques of _______ overcome the limitation of traditional hybridization procedures.

• immunology

• modern hybridization

• genetic engineering

• cell biology

Answer explanation

Answer: c
Explanation: Traditional hybridization procedures lead to the inclusion and multiplication of undesirable genes along with the desired genes. The techniques of genetic engineering such as recombinant DNA, use of gene cloning and gene transfer overcome the limitation of traditional hybridization procedures.

What initiates the replication in DNA?

• DNA ligase

• Origin of replication

• Termination sequences

• Histone proteins

Answer explanation

Answer: b
Explanation: In a chromosome, there is a specific DNA sequence called the origin of replication, which is responsible for initiating replication. DNA ligase is an enzyme which helps in joining of DNA. Termination sequences are the site at which DNA replication terminates while histones are the proteins around which DNA is wound.

_____ is an autonomously replicating circular extra-chromosomal DNA.

• Bacteria

• Nitrogenous base

• RNA

• Plasmid

Answer explanation

Answer: d
Explanation: Plasmid is typically a small circular DNA strand in the cytoplasm of a bacterium or protozoan. It is a genetic structure in a cell that can replicate independently of the chromosomes. They are commonly used in recombinant DNA technology.

Restriction enzymes are _______

• ligases

• sticky ends

• molecular scissors

• vectors

Answer explanation

Answer: c
Explanation: Restriction enzymes are molecular scissors. They are also known as restrictase. They are short nucleotide sequences that recognize the specific sites and cleave the DNA at or near specific recognition sites within molecules.

Plasmid DNA acts as _____ to transfer the piece of DNA attached to it into the host organism.

• vector

• protein

• carrier

• antibody

Answer explanation

Answer: a
Explanation: A vector is a DNA molecule used as a vehicle to artificially carry foreign genetic material into another cell. Plasmid DNA is commonly used as a vector to insert the gene of interest in the desired organism.

Making multiple copies of the desired DNA template is called ______

• transferring

• cloning

• r-DNA technology

• genetic engineering

Answer explanation

Answer: b
Explanation: The term cloning means making multiple copies of the desired DNA template which are genetically identical. This process can be natural or artificial. The clone then replicates itself inside the host body.

______ organism’s plasmid was used for the construction of first recombinant DNA.

• Cyanobacteria

• Bacillus subtilis

• Saccharomyces cerevisiae

• Salmonella typhimurium

Answer explanation

Answer: b
Explanation: The first recombinant DNA was constructed by linking a gene encoding antibiotic resistance with a native plasmid of Salmonella typhimurium. This experiment was successfully conducted by Stanley Cohen and Herbert Boyer in 1972.

In genetic engineering, restriction enzymes cleave the DNA at a specific site known as _____

• restriction

• recognition

• promoter

• sense

Answer explanation

Answer: b
Explanation: Restriction enzymes cleave the DNA at a specific sequence known as recognition sequence. These sequences are highly specific for each enzyme.