1. Biotechnology, in its broad sense, is best described as the use of
ⓐ. genetically modified microorganisms used to produce industrial products
ⓑ. living organisms, cells or enzymes used to make useful products and processes
ⓒ. isolated DNA molecules used to diagnose inherited disorders in humans
ⓓ. chemical catalysts alone used to manufacture products of biological origin
Correct Answer: living organisms, cells or enzymes used to make useful products and processes
Explanation: Biotechnology has a broad meaning that includes the use of living organisms, cells or enzymes to obtain products and processes useful to humans. It is therefore not restricted only to recombinant DNA technology or genetically modified organisms. Traditional microbial processes as well as modern molecular techniques can fall within this broader concept. This broad framing is important because a process can qualify as biotechnology even when it does not involve deliberate gene cloning, provided biological systems or their components are used to achieve a useful outcome.
2. A student groups the following processes as examples of biotechnology:
P: Conversion of milk into curd by microorganisms
Q: Production of bread using microbial fermentation
R: Manufacture of wine through microbial activity
S: Formation of common salt by evaporation of seawater
Which grouping is correct?
ⓐ. Q, R and S only
ⓑ. P and S only
ⓒ. P, Q and R only
ⓓ. P, Q, R and S
Correct Answer: P, Q and R only
Explanation: Curd, bread and wine involve biological activity, particularly the use of microorganisms, and therefore represent traditional biotechnology. Evaporation of seawater to obtain salt is a physical process and does not depend on organisms, cells or enzymes. Thus only P, Q and R fit the broad biotechnology concept. The distinction rests on the mechanism of production: microbial metabolism drives the first three processes, whereas salt recovery by evaporation does not require a biological agent.
3. The word biotechnology is sometimes used in a more restricted modern sense. In this usage, the emphasis is primarily on
ⓐ. domesticated plants and animals used in all human activities
ⓑ. genetically modified organisms used in appropriately scaled processes
ⓒ. natural microbial fermentation carried out without deliberate manipulation
ⓓ. industrial chemical processes that produce organic compounds
Correct Answer: genetically modified organisms used in appropriately scaled processes
Explanation: Although biotechnology broadly includes many traditional biological processes, its modern restricted use commonly emphasises genetically modified organisms and large-scale biological processing. This distinction prevents the broader historical meaning of biotechnology from being confused with its more specialised modern usage. The narrower usage therefore highlights deliberate biological manipulation and controlled production without erasing the older, broader meaning of the term.
4. According to the European Federation of Biotechnology, the most appropriate description of biotechnology is
ⓐ. integration of genetic engineering with cells solely to produce therapeutic proteins
ⓑ. integration of natural sciences with organisms, cells or molecular analogues for products and services
ⓒ. integration of microbial cultivation with organisms solely to produce antibiotics at industrial scale
ⓓ. integration of synthetic chemistry with non-living systems to replace organisms in biological production
Correct Answer: integration of natural sciences with organisms, cells or molecular analogues for products and services
Explanation: The European Federation of Biotechnology gives biotechnology a broad definition. It integrates natural science with organisms, cells, their parts and molecular analogues to produce products and services. The definition is therefore wider than genetic engineering alone and also wider than microbial industrial production alone. Its wording deliberately includes more than whole organisms, allowing cellular components and molecular analogues to contribute to useful technological outcomes.
5. Consider the following statements about the formal scope of biotechnology:
I. Whole organisms may be used.
II. Cells or parts of cells may be used.
III. Molecular analogues may be involved.
IV. The outcome may include products as well as services.
Which option is correct?
ⓐ. I and II only
ⓑ. II and III only
ⓒ. I, II and IV only
ⓓ. I, II, III and IV
Correct Answer: I, II, III and IV
Explanation: The EFB definition intentionally gives biotechnology a wide scope. It includes organisms, cells, their parts and molecular analogues, and it connects their use with both products and services. Restricting biotechnology only to intact organisms or only to commercial products would therefore be too narrow. Taken together, the four statements show why the formal definition cannot be reduced to genetic engineering alone or to the use of intact organisms only.
6. A textbook introduces in vitro fertilisation, synthesis and use of a gene, DNA vaccination and correction of a defective gene while explaining modern biotechnology. These examples are best interpreted as
ⓐ. modern biotechnology examples showing the broad scope of the field
ⓑ. processes all based on one identical recombinant-DNA procedure
ⓒ. traditional biotechnology examples based mainly on fermentation
ⓓ. processes restricted to large-scale cultivation of microorganisms
Correct Answer: modern biotechnology examples showing the broad scope of the field
Explanation: These examples illustrate the diversity of modern biotechnology. They do not all represent one identical mechanism, nor are they traditional fermentation processes. At this stage, their role is to illustrate the broad range of modern biological manipulation without requiring detailed application-level mechanisms. Their inclusion shows that modern biotechnology covers several kinds of biological manipulation, so the examples should be treated as breadth indicators rather than as one common experimental protocol.
7. Match the two major foundations of modern biotechnology with their principal roles:
P: Genetic engineering
Q: Bioprocess engineering
I: Deliberate alteration and transfer of genetic material
II: Maintenance of contamination-free conditions for large-scale production
ⓐ. P-I, Q-II
ⓑ. P-II, Q-I
ⓒ. P-I, Q-I
ⓓ. P-II, Q-II
Correct Answer: P-I, Q-II
Explanation: Genetic engineering deals with deliberate modification or transfer of genetic material so that a host acquires a desired genetic change. Bioprocess engineering provides the controlled and sterile conditions required to grow selected cells or microorganisms at a useful scale. Modern biotechnology commonly depends on both foundations rather than either one alone. Genetic engineering establishes the desired genetic change, while bioprocess engineering creates the controlled production environment in which selected cells can generate useful quantities of product.
8. A DNA segment is deliberately altered and then introduced into a host cell so that the host displays a new inherited characteristic. The central biotechnology technique illustrated here is
ⓐ. conventional fermentation
ⓑ. downstream processing
ⓒ. genetic engineering
ⓓ. gel electrophoresis
Correct Answer: genetic engineering
Explanation: Genetic engineering involves deliberate alteration of the chemistry of genetic material followed by its introduction into a host organism to produce a changed phenotype or genetic state. Downstream processing concerns product recovery, while gel electrophoresis separates DNA fragments rather than producing the genetic alteration described. The defining feature is therefore purposeful manipulation and transfer of genetic information, not merely growth of cells or recovery of a product after production.
9. Two laboratories work with the same microorganism. Laboratory P changes its genetic material before introducing it into a host strain. Laboratory Q grows a selected strain under carefully controlled sterile conditions to manufacture a biological product. The major techniques emphasised by P and Q, respectively, are
ⓐ. bioprocess engineering and genetic engineering
ⓑ. genetic engineering and bioprocess engineering
ⓒ. downstream processing and genetic engineering
ⓓ. genetic engineering and gel electrophoresis
Correct Answer: genetic engineering and bioprocess engineering
Explanation: Laboratory P is modifying and transferring genetic material, which is the defining role of genetic engineering. Laboratory Q is concerned with controlled, contamination-free cultivation for production, which is the domain of bioprocess engineering. The two techniques complement each other in many modern biotechnology processes. The comparison separates modification of hereditary material from the controlled cultivation needed to turn a selected biological system into a productive process.
10. A production vessel has the correct nutrient medium and temperature, but unwanted microorganisms repeatedly enter the culture containing the desired cells. The biotechnology principle most directly compromised is
ⓐ. failure of DNA-fragment joining by DNA ligase
ⓑ. failure to generate genetic variation during sexual reproduction
ⓒ. failure of foreign-DNA replication from a functional origin
ⓓ. loss of sterility during large-scale bioprocessing
Correct Answer: loss of sterility during large-scale bioprocessing
Explanation: Large-scale cultivation of selected microbial or eukaryotic cells requires sterile conditions so that only the desired culture grows. Contaminants can compete for nutrients, alter the culture environment and interfere with product formation. The failure described is therefore a bioprocess-engineering problem rather than a DNA manipulation problem. Because contamination changes the biological population inside the vessel, even correctly engineered production cells may lose yield or product quality if sterility is not maintained.
11. Why is sterility particularly important when desired cells are grown for large-scale biotechnology production?
ⓐ. It prevents genetically different DNA molecules from entering the vessel.
ⓑ. It converts every cultured cell into a recombinant production cell.
ⓒ. It allows foreign DNA to replicate without a functional origin of replication.
ⓓ. It prevents unwanted organisms from growing with the production culture.
Correct Answer: It prevents unwanted organisms from growing with the production culture.
Explanation: Sterile conditions are used to prevent contamination of the desired culture by other microorganisms. Large-scale production depends on maintaining the selected cells under controlled conditions so that biomass and product formation can proceed predictably. Sterility does not itself cause transformation, recombination or DNA replication. Sterility is therefore a population-control requirement during cultivation: it protects the intended production culture from biological competitors or contaminants.
12. The relevance of sexual and asexual reproduction to the conceptual basis of genetic engineering is best represented by the statement that
ⓐ. sexual reproduction creates new genetic combinations, while asexual reproduction largely preserves parental information
ⓑ. asexual reproduction creates greater genetic variation, while sexual reproduction largely preserves parental information
ⓒ. sexual and asexual reproduction both generate identical genetic combinations in every generation
ⓓ. sexual reproduction blocks gene transmission, while asexual reproduction alone transmits genes
Correct Answer: sexual reproduction creates new genetic combinations, while asexual reproduction largely preserves parental information
Explanation: Sexual reproduction combines genetic material from different parents and therefore generates new combinations and variation. Asexual reproduction generally transmits genetic information with much greater continuity. This contrast helps explain why controlled manipulation of particular genes can be useful when a specific genetic change is desired. This genetic contrast provides the background for understanding why selective DNA manipulation can be preferable when a specific hereditary change must be introduced and maintained.
13. A breeder crosses two organisms because one parent carries a desired gene. The offspring receive the desired gene but also several unwanted genes from the same parent. This outcome illustrates a major limitation of
ⓐ. vector replication inside a suitable host cell
ⓑ. DNA ligation during recombinant construction
ⓒ. conventional hybridisation of parental organisms
ⓓ. bioprocess engineering of production cultures
Correct Answer: conventional hybridisation of parental organisms
Explanation: Conventional hybridisation transfers groups of genes through reproduction rather than transferring only one precisely selected DNA sequence. Consequently, desirable genes may be inherited together with undesirable ones. Genetic engineering can provide greater selectivity by allowing one gene or a defined set of genes to be introduced more directly. The problem is not that hybridisation cannot transfer the desired gene, but that recombination and linkage can cause additional donor genes to accompany it.
14. A researcher wants to transfer only a defined gene responsible for a useful trait while minimising the simultaneous introduction of unrelated genes from the donor. The approach that most directly addresses this objective is
ⓐ. sterile cultivation without genetic manipulation
ⓑ. random transfer by conventional hybridisation
ⓒ. continued asexual propagation of the donor
ⓓ. selective transfer by genetic engineering
Correct Answer: selective transfer by genetic engineering
Explanation: Genetic engineering permits selected DNA sequences to be isolated, manipulated and introduced into a suitable host. Conventional hybridisation may transfer many donor genes together, including undesirable ones. Sterile cultivation improves production conditions but does not provide the selective gene-transfer advantage required in this situation. This selectivity is especially valuable when the objective is to alter one defined trait without transferring a large, uncontrolled set of donor genes.
15. A foreign DNA fragment successfully enters a bacterial cell but remains separate from DNA capable of replicating in that host. If no additional mechanism supports its replication, the most likely long-term outcome is that the foreign DNA
ⓐ. will be copied and inherited indefinitely after entry
ⓑ. may be lost because entry does not ensure replication
ⓒ. will integrate into the bacterial chromosome after entry
ⓓ. will become a self-replicating plasmid after entry
Correct Answer: may be lost because entry does not ensure replication
Explanation: Mere entry of alien DNA into a cell does not guarantee its stable maintenance. For the foreign DNA to persist as cells divide, it must be associated with genetic material capable of replication in the host or otherwise become part of a replicating system. Without such replication support, the introduced DNA may fail to be transmitted to progeny. Stable cloning therefore requires more than successful DNA uptake; the introduced sequence must become part of a genetic system that is copied as the host lineage continues.
16. In an experiment, two identical foreign DNA fragments enter separate host cells. Fragment P is linked to a host-compatible replicating DNA molecule, whereas fragment Q remains unsupported. After many generations, P is repeatedly recovered but Q is usually absent. The most appropriate inference is that
ⓐ. alien DNA persists when it can replicate within the host
ⓑ. all incoming DNA becomes part of the host chromosome
ⓒ. unsupported alien DNA is preferentially amplified by the host
ⓓ. alien DNA persistence depends mainly on the size of the fragment
Correct Answer: alien DNA persists when it can replicate within the host
Explanation: Fragment P persists because it is associated with DNA that can replicate inside the host. As cells divide, replication permits copies of the foreign sequence to be passed on. Fragment Q entered the cell but lacked comparable replication support, demonstrating why successful entry and stable inheritance are distinct requirements. The experiment separates two events that are often confused: transformation places DNA inside a cell, whereas replication enables that DNA to persist and increase in copy number.
17. Assertion: Introduction of alien DNA into a host cell does not by itself guarantee that the DNA will be maintained in subsequent generations.
Reason: Stable multiplication of alien DNA generally requires its association with DNA that can replicate in the host.
ⓐ. Both are true, and Reason correctly explains Assertion.
ⓑ. Both are true, but Reason does not correctly explain Assertion.
ⓒ. Assertion is true, but Reason is false.
ⓓ. Assertion is false, but Reason is true.
Correct Answer: Both are true, and Reason correctly explains Assertion.
Explanation: Both statements are correct and causally related. DNA that merely enters a cell may not be duplicated when the host divides. Association with a host-compatible replicating DNA molecule provides the replication capacity needed for repeated copying and maintenance, explaining why entry alone is insufficient. The reason directly explains the assertion because cell division will dilute or eliminate unsupported DNA unless the introduced sequence is copied along with a replicating genetic element.
18. The origin of replication, or ori, is important in recombinant DNA technology because it is
ⓐ. the enzyme that cuts DNA at recognition sequences
ⓑ. the site that directly joins two DNA fragments together
ⓒ. the marker that always distinguishes recombinant from non-recombinant cells
ⓓ. the sequence from which replication of linked DNA is initiated
Correct Answer: the sequence from which replication of linked DNA is initiated
Explanation: An origin of replication is a DNA sequence that permits replication to begin. A foreign DNA fragment linked to a suitable replicon containing an ori can therefore be copied along with that DNA inside the host. Ligases join DNA, restriction enzymes cut DNA and selectable markers serve different functions. Thus ori is a property of the DNA replicon, not an enzyme, and its presence links the fate of an inserted sequence to the replication behaviour of the vector.
19. A circular DNA vector enters a bacterial cell and carries a foreign DNA insert, but its functional ori has been removed. Assuming no alternative replication origin is available, the most direct consequence is
ⓐ. efficient independent multiplication of the vector and insert
ⓑ. automatic ligation of the vector into the chromosome
ⓒ. failure of the vector to replicate autonomously in the host
ⓓ. conversion of the foreign DNA into a selectable marker
Correct Answer: failure of the vector to replicate autonomously in the host
Explanation: The ori provides the starting point required for replication of the vector DNA. If the vector lacks a functional origin recognised by the host, it cannot normally maintain autonomous replication. Consequently, the linked foreign DNA also loses the replication advantage that makes cloning possible. Removing ori therefore disrupts the maintenance mechanism even if the selectable marker, cloning site and foreign insert remain physically present on the plasmid.
20. Two otherwise suitable vectors differ mainly in their replication behaviour. Vector P is maintained at relatively few copies per transformed cell, whereas vector Q is maintained at many more copies. If the goal is to recover a large amount of an inserted DNA sequence, Q may be preferred because
ⓐ. higher vector copy number can yield more copies of the linked insert
ⓑ. high vector copy number eliminates the need for DNA replication
ⓒ. high vector copy number guarantees expression of every inserted gene
ⓓ. vector copy number determines whether DNA ligase can join fragments
Correct Answer: higher vector copy number can yield more copies of the linked insert
Explanation: Once a foreign DNA fragment is linked to a replicating vector, copies of the vector also carry copies of the insert. A vector maintained at a higher copy number can therefore provide more recoverable copies of the target DNA. This is a cloning advantage and should not be confused with expression of the encoded gene product. Copy number affects DNA yield rather than automatically determining gene expression, because expression also depends on whether the inserted gene is functionally transcribed and translated in the host.
