Practice Questions

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#Question id: 5654

Two human disorders, Prader-Willi syndrome and Angelman syndrome, occur when a small deletion in a specific region of chromosome 15 is contributed by either the father or mother, respectively. Why does this small deletion not behave as a recessive allele for either syndrome, that is, why is its loss not made up for by the good copy of the region on chromosome 15 contributed by the other parent?

#Unit 5. Developmental Biology

This portion of chromosome 15 is invariably mutated, so the other parent contributes recessive alleles that are thus homozygous and perturb development.
The copy of chromosome 15 from the other parent has genes in the region of the deletion that are imprinted, and thus inactive; in the absence of any active copies of these genes, development cannot proceed normally.
The genes in this portion of chromosome 15 are special in that they are required in two copies for normal development, and so the loss of one set does not allow normal development.
Chromosomes with deletions do not go through mitosis correctly, so cell divisions in the embryo result in cells with abnormal numbers of chromosomes, and these cells do not contribute properly to the development of the organism.

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TLS Online TPP Program

#Question id: 23461

#General Aptitude

Statement— Should young entrepreneurs be encouraged?

I) Yes. They will help in industrial development of the country.

II) Yes. They will reduce the burden on employment market.

TLS Online TPP Program

#Question id: 23462

#General Aptitude

Statement— Should all the annual examinations up to Std. V be abolished?

I)Yes the young student should not be burdened with such examinations which hampers their natural growth.

II) No. The students will not study seriously as they will get automatic promotion to the next class and this will affect them in future.

TLS Online TPP Program

#Question id: 23463

#General Aptitude

Statement— Should Indian scientists working abroad be called back to India?

I) Yes. They must serve the motherland first and forget about discoveries, honours, facilities and all.

II) No. We have enough talent; let them stay where they want.

TLS Online TPP Program

#Question id: 23464

#General Aptitude

Statement— Should we scrap the system of formal education beyond graduation?

I) Yes. It will mean taking employment at an early date.

II) No. It will mean lack of depth of knowledge.

TLS Online TPP Program

#Question id: 23465

#General Aptitude

Statement— Should there be an upper age limit of 65 years for contesting Parliamentary/ Legislative Assembly elections?

I) Yes. Generally, people above the age of 65 lose their dynamism and will power.

II) No. The life span is so increased that people remain physically and mentally active even up to the age of 80.

TLS Online TPP Program

#Question id: 23466

#General Aptitude

Statement— Should new big industries be started in Mumbai?

I) Yes. It will create job opportunities.

II) No. It will further add to the pollution of the city.