Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
A transgenic mouse expressing a human growth hormone gene exhibits gigantism. Researchers discover a second transgenic mouse line with the same human growth hormone gene construct, yet these mice show normal growth. Which of the following is the MOST LIKELY explanation for this discrepancy?
The second mouse line has a mutation in the mouse growth hormone receptor gene.
The human growth hormone gene is not being transcribed in the second mouse line.
Position effect variegation due to the transgene's insertion site in the second mouse line.
The second mouse line expresses an endogenous inhibitor of human growth hormone.
Which technique is NOT typically used for the production of transgenic animals?
Microinjection of DNA into the pronucleus of a fertilized egg
Retroviral infection of embryonic stem cells
Electroporation of fertilized eggs with recombinant DNA
Transfer of genetically modified embryonic stem cells into a blastocyst
A researcher aims to create a transgenic cow that produces human lactoferrin in its milk. Which promoter would be MOST suitable to drive the expression of the human lactoferrin gene in the mammary gland of the cow?
CMV promoter
ฮฒ-actin promoter
ฮฒ-lactoglobulin promoter
Metallothionein promoter
Knockout mice lacking the gene for PrP (prion protein cellular form) are resistant to prion diseases. What can be directly concluded from this observation?
PrP is sufficient to cause prion diseases.
PrP is the infectious agent in prion diseases.
PrP is necessary for the development of prion diseases.
The absence of PrP enhances the immune response against prions.
Which of the following is a major ethical concern associated with the production of transgenic animals?
The high cost of producing transgenic animals.
The low success rate of creating transgenic animals.
Animal welfare and the potential for unforeseen health problems in the transgenic animals.
The limited applicability of transgenic animal models to human diseases.
A transgenic animal is created by inserting a gene for enhanced muscle growth into its genome. However, the resulting offspring show a variety of phenotypes, some with significantly enhanced muscle growth, others with moderate enhancement, and some with no change at all. Which phenomenon is MOST likely responsible for this phenotypic variation?
Incomplete penetrance of the transgene
Pleiotropic effects of the transgene
Variable transgene copy number and integration sites
Epigenetic silencing of the transgene in some individuals
Rosie the cow was a transgenic animal produced by which technique?
Retroviral infection
Biolistic gene transfer
Microinjection
Embryonic stem cell transfer
Which of the following is NOT a potential benefit of producing transgenic animals?
Production of valuable proteins in milk
Disease resistance in livestock
Improved growth rates in animals
Increased biodiversity in natural ecosystems
Transgenic animals are used as model organisms to study human diseases. Which aspect makes them suitable for this purpose?
They have shorter lifespans than humans.
They are easier to maintain in laboratory settings than humans.
They can be genetically modified to mimic human disease conditions.
They are ethically less concerning to experiment on than humans.
What is the role of a 'reporter gene' in the production of transgenic animals?
It encodes the protein of interest.
It helps identify cells that have successfully incorporated the transgene.
It promotes the integration of the transgene into the host genome.
It silences the expression of other genes.
