Question

 

QUESTION 31

The difference between the genome of HIV and the genome of coronaviruses is that

		HIV is DNA virus, whereas coronaviruses are retroviruses
		The DNA genome of the coronaviruses can insert in a host chromosome, but the DNA of HIV cannot.
		The RNA genome of HIV is reverse transcribed into DNA, whereas the RNA of a coronavirus is not.
		The HIV genome is single-stranded DNA, while the coronavirus genome is double-stranded DNA.
		There is no difference between HIV and coronaviruses, they are the same.

QUESTION 32

Which one of the molecular events below does NOT have to do with epigenetic changes in the genome?

		Histone acetylation
		DNA methylation
		Histone de-acetylation
		High-level expression of a gene resulting from the phosphoylation of the gene's protein product.
		Heterochromatin formation

QUESTION 33

Regulatory elements are_________:

		Protein molecules that interact with DNA to regulate transcription
		Ion-gated channels on the cytoplasmic membrane
		Specific nucleotide sequences within the DNA at which transcription factors bind
		RNA-induced silencing complex
		telomerase enzymes

QUESTION 34

The RAS allele of bladder carcinoma is a(n) ________ which acts as a _________allele in conferring cancerous phenotype on cells.

		mutated tumor suppressor gene; recessive
		oncogene; recessive
		mutated tumor suppressor gene; dominant
		oncogene; dominant
		none of the above

QUESTION 35

Your beloved horse got hit by a truck and she is badly hurt. The vet says he has to put her to sleep. You decide to have a clone made of her, so you ask the vet to collect some live cells from her body. What is the purpose of these cells?

		These cells will treated with transcription factors Oct4, Klf4, Sox2, c-Myc to turn them into tumor cells.
		These cells will be used to extract DNA and used for the construction of a genomic library.
		These cells will be used to extract RNA and used for the construction of a cDNA library.
		The cells will serve as a source of nuclei to be transferred to an enucleated (nucleus-less) egg cell which will be induced to form an embryo.
		None of the above has anything to do with creating a clone of your horse.

QUESTION 36

A bacterium which contains an entire F factor integrated into its chromosome is called a(n)_________.

		Hfr cell
		Fâ factor
		Competent cell
		Incompetent cell
		totipotent cell

QUESTION 37

In female mammals, one of the X chromosomes becomes transcriptionally mostly inactive and heterochromatic. The expression of which RNA molecule is associated with keeping the inactive X chromosome heterochromatic?

		The Xist RNA
		The Tsix RNA
		The Yist RNA
		The Marxist RNA
		The leftist RNA

QUESTION 38

In human DNA, heavy methylation of C nucleotides is associated with

		mRNA stability
		High transcription rate
		Low transcription rate
		cAMP-mediated regulation of the lac operon
		arrogance

QUESTION 39

The regulation of the lac operon by the LacI protein is

		Negative inducible
		Positive inducible
		Negative repressible
		Positive repressible
		Hopelessly incomprehensible

QUESTION 40

The spread of cancer cells to other parts of the body is known as

		Tumor suppression.
		carcinogen.
		angiogenesis.
		Contact inhibition.
		metastasis.

Answer 1

31, 3.The RNA of genome of HIV is reverse transcribed into DNA,whereas the Rna of corona virus i not.

Both HIV and Corona virus are RNA viruses,but only HIV is a retrovirus which can perform reverse transcription ( DNA from RNA).BOTH virus infect cell by inserting viral genome into host cell.

32, 5. Heterochromatin formation

Epigenetic change is heritable change in gene expression with out change in genotype.Heterochromatin formation is naturally occuring process in nucleus of eukaryotic cells ( at centromeres) that silence gene expression.

33, 3. Specific nucletide sequence with in DNA at which transcription factors bind.

These regulatory elements include promoter,enhancer and silencerwhich act as regulatory region of gene.

36, 1. Hfr cell (High frequency recombination cell)

This is bacterium with a conjugative plasmid integreted intochromosomal DNA through homologous recombination.

Cells which have high capacity for binding DNA to surface are Competent cell and does bind for DNA are called In competent.Totipotent cells are cell having capacity to form an entire organism.

39, 1. negative inducible

The lacl gene produces protein that block RNAP from binding to promoter of operon.Here the gene is turned off by the regulatory factor unless lactose is added hence called negative inducible.

40, 5. metastasis, the spread of cancer from primary site to other part ie, development of secondary malignancy.

Tumour suppression is regulation of cell durind cell division and replication. Carcinogens are substance cause cancer in living tissue. Angiogenesis is the process through which new blood vessels are formed from pre-existing vessels in earlier stage of vasculogenesis. Contact inhibition Is ceasing of proliferation and growth of non cancerous cell when they contact each other.