Question

ANSWER ALL QUESTIONS FOR GOOD RATING :)

QUESTION 13

A mating between a male donkey and a female horse results in a mule, but the reciprocal mating leads to a phenotypically different hybrid, named hinny. The reason for the phenotypic difference between mules and hinnies is due to

		The different number of chromosomes in the hinny and the mule
		The differential sex-specific methylation of the DNA in the gametes of the horse and the donkey
		The presence of plasmid DNA in cytoplasm of the donkeyâ s egg cell.
		The absence of mitochondrial DNA in horseâ s sperm.
		Hinnies are fed with royal jelly, whereas mules with ordinary honey

  

QUESTION 14

Which of the following statements about oncogenes is/are true?

		They are mutant alleles of genes that normally function to positively regulate the cell cycle and promote cell division.
		Their wild-type progenitors are referred to as proto-oncogenes.
		They act as dominant alleles in contributing to the cancer phenotype.
		All of the above.
		None of the above.

  

QUESTION 15

Which RNA molecule is synthesized when an RNA polymerase transcribes this template DNA strand: 5â -GTCA-3â ? Watch the orientation: transcripton from template DNA to RNA

		5â -ACGU-3â
		5'-UGCA-3'
		5'-TCGA-3'
		5'-TGCA-3'
		5â -UGAC-3â

QUESTION 16

During initiation of translation, how does the small ribosomal subunit identifies the site of the first codon in prokaryotes?

		It scans the mRNA from 5â to 3â until it finds a sigma factor attached to the first codon.
		It scans the mRNA from 5â to 3â until it finds a charged tRNA attached to the first AUG codon.
		It scans the mRNA until it finds a release factor attached to the first AUG codon.
		It recognizes the site of the first AUG codon by the presence of the Kozak consensus sequence.
		It binds to the Shine-Delgarno sequence (AGGAGG) of the mRNA.

QUESTION 17

When genes are _______________, the proportion of parental and recombinant types are equal in the dihybrid test cross progeny.

		located on separate non-homologous chromosomes
		assorting independently
		located on the same chromosome, but very far apart (>50 map units)
		All of the above
		Only a and b are correct answers.

  

QUESTION 18

How many chromosomes are in the secondary oocyte of the gray wolf (Canis lupus) which has 78 chromosomes in its diploid somatic cells?

		156
		78
		39
		19.5
		4

QUESTION 19

Which one of these chromatin modifications is invariably associated with REPRESSED transcription of genes?

		DNA methylation
		DNA de-methylation
		Histone phospholrylation
		Chromatin remodeling
		istone acetylation

  

QUESTION 20

What is p53?

		A proto-oncogene
		A cyclin-dependent kinase
		A cyclin
		A tumor suppressor gene
		A protein that removes acetyl groups from DNA

Answer 1

13. Differential sex specific methylation of DNA in gametes of horse and donkey. This is called imprinting.

14. All of the above. Protooncogene due to gain of mutation get converted into oncogenes and promote cell cycle progression.

15. Ideally 5' GUCA 3' Should be synthesized as mRNA , you can match the sequence from the option that ressembles the answer most.

16. It recognise the site of first AUG codon by the presence of Kozak consensus sequence.

17. All of the above.

18. 39. Because oocyte is haploid.

19. DNA methylation.

20. A tumor supressor gene.