Questions
Chiasmata formation in Drosophila
- generally takes place in males and females
- takes place only in males
- never or rarely takes place in males
- never or rarely take place in females
In which of the following crosses will the progenies obtained be fifty percent homozygous recessive and fifty percent heterozygous?
- TT x Tt
- Tt x Tt
- Tt x tt
- TT x tt
Haploid chromosome number is 10. What will be its monosomy?
- 18
- 19
- 21
- 17
- 23
Directions: The following question has four choices out of which ONLY ONE is correct.
The genetic codes representing amino acid valine are
- GGU,GGC,GGA,GGG
- CUU,CUC,CUA,CUG
- GCU,GCC,GCA,GCG
- GUU,GUC,GUA,GUG
- GCU,GCC,GCA,GGG
‘Gametes are never hybrid’. It is a statement of the law of
- dominance
- segregation
- independent assortment
- random fertilisation
- linkage
A Barr body is present in a male child. The syndrome most likely to occur is
- Klinefelter’s syndrome
- Down’s syndrome
- Turner's syndrome
- Edward’s syndrome
- Trisomy
A cross between yellow round and green wrinkled seed pea plants gave the following four types of progeny in equal proportions: yellow round, yellow wrinkled, green round and green wrinkled. The genotypes of the parents in this case must be
- YYRR X yyrr
- YyRr X yyrr
- YYRR X YYRR
- YyRr X YYRR
- yyrr X yyrr
DNA generally acts as a template for the synthesis of
- protein only
- DNA only
- RNA only
- RNA and DNA both
Sex-influenced genes are coded by
- autosomal genes
- X linked genes
- Y linked genes
- epistatic genes
- none of the above
Phenylketonuria is a genetic disorder of
- trisomic condition
- monosomic dominant gene
- autosomal dominant gene
- autosomal recessive gene
- None of these
Which of the following is a living fossil?
- Euglena
- Limulus
- Sycon
- Balanoglossus
- Herdmania
Teminism is a phenomenon which refers to
- mutual activity of operator and promoter genes
- central biological dogma
- reverse transcription
- transduction in bacteria
Xenia refers to
- effect of pollen on stem
- effect of pollen on taste of fruit
- effect of pollen on vascular tissue
- effect of pollen on endosperm
- effect of pollen on leaves
When chromosome sets are present in multiples of ‘n’, the condition is called
- polyploidy
- aneuploidy
- euploidy
- diploidy
- monoploidy
Which of the following chromosome numbers is present in a trisomic individual?
- 2n + 1
- 2n - 1
- 2n - 2
- 2n + 2
In DNA, two nucleotides are linked by
- hydrogen bonds
- peptide bonds
- disulphide bonds
- phosphate diester bonds
Loss of one chromosome from one set is called
- tetrasomy
- nullisomy
- monosomy
- trisomy
The addition or deletion of one or more chromosomes in a set is called
- euploidy
- aneuploidy
- polyploidy
- heteroploidy
‘Homo erectus’ is the zoological name of
- Cro-Magnon man
- Peking man
- Nut cracker man
- Neanderthal man
- None of the above.
Theory of spontaneous creation was supported by
- Van Helmont
- Redi
- Spallanzani
- Pasteur