Recent questions tagged molecular-biology-and-genetics

Which of the following combinations of plant hormones and their associated function are $\text{CORRECT}$?$$\begin{array}{|l|l|l|} \hline & \textbf{Hormone} & \textbf{Func...

Which one of the following tools is used to compare all the possible six-open reading frames of a given nucleotide query sequence with all the available six-open reading ...

In $\textit{Neurospora crassa}$, a mutation in the $\textit{poky}$ gene results in a slow growth phenotype (poky). The results of four crosses are given below.wild-type $...

Tertiary structure of a protein consisting of $\alpha$-helices and $\beta$-strands can be determined bycircular dichroism spectroscopymass spectrometrynuclear magnetic re...

Which of the following chemical messenger(s) is/are derivative(s) of tryptophan?$\gamma$-amino butyric acidIndole acetic acidMelatoninSerotonin

A $\text{DNA}$ solution of $50 \: \mu g \: mL^{-1}$ concentration gives an absorbance of $1.0$ at $260 \textit{ nm}$. An aliquot of $20 \: \mu L$ from a $50 \: \mu L$ pur...

The possible number of $\textit{Sal}\text{I}$ restriction sites in a $9\text{ kb}$ double-stranded $\text{DNA}$, with all four bases occurring in equal proportion (rounde...

For site-directed mutagenesis, which one of the following restriction enzymes is used to digest methylated $DNA$?$KpnI$$DpnI$$XhoI$$MluI$

Which of the following statements are $CORRECT$ when a protein sequence database is searched using the $BLAST$ algorithm?A larger E-value indicates higher sequence simila...

Which one of the following is coded by the $ABO$ blood group locus in the human genome?Acyl transferaseGalactosyltransferaseTransposase$\beta$-Galactosidase

Which of the following factors affect the fidelity of $DNA$ polymerase in polymerase chain reaction?$Mg^{2+}$ concentration$pH$Annealing temperature$P$ and $Q$ only$P$ an...

$Group\; I$ lists spectroscopic methods and $Group\; II$ lists biomolecular applications of these methods. Match the methods in $Group\; I$ with the applications in $Grou...

Which of the following statements are CORRECT about the function of fetal bovine serum in animal cell culture?lt stimulates cell growthIt enhances cell attachmentlt provi...

Which one of the following covalent linkages exists between $7$-Methyl guanosine $(m^{7}G)$ and $mRNAs$?${2}'-{3}'$ triphosphate${3}'-{5}'$ triphosphate${5}'-{5}'$ tripho...

The molecular mass of a protein is $22\:kDa$. The size of the $\text{cDNA}$ (excluding the untranslated regions) that codes for this protein is __________ $kb$ (rounded o...

Which of the following statements about immune response are $CORRECT$?$T$ cells are activated by antigen-presenting cellsForeign peptides are not presented to helper $T$ ...

Which of the following statemets are $CORRECT$ about eukaryotic cell cycle?$CDKs$ can phosphorylate proteins in the absence of cyclins$CDKs$ can be inactivated by phospho...

$W,X$ and $Y$ are the intermediates in a biochemical pathway as shown below:$$S \cdots \cdots \rightarrow W\rightarrow X\rightarrow Y\rightarrow Z$$Mutants auxotrophic fo...

Determine the correctness or otherwise of the following Assertion [$a$] and the Reason [$r$].Assertion [$a$]: Embryonic stem cells are suitable for developing knockout mi...

The schematic of a plasmid with a gap in one of the strands is shown below:Which of the following enzyme(s) is/are required to fill the gap and generate a covalently clos...

Which of the following strategies are used by cells for metabolic regulation?Phosphorylation-dephosphorylationAllosteryFeedback inhibition$P$ and $Q$ only$P$ and $R$ only...

Determine the correctness or otherwise of the following Assertion [$a$] and the Reason [$r$].Assertion [$a$]: A zygote and its immediate descendant cells are unspecialize...

Which of the following statements about gene therapy are CORRECT?Affected individuals, but not their progeny, can be cured through germline gene therapyAffected individua...

The sequence of a $1$ $Mb$ long $DNA$ is random. This $DNA$ has all four bases occurring in equal proportion. The number of nucleotides, on average, between two successiv...

$E$ coli was grown in $^{15}N$ medium for several generations. Cells were then transferred to $^{14}N$ medium, allowed to grow for $4$ generations and $DNA$ was isolated ...

The amino acid sequence of a peptide is $Phe-Leu-lle-Met-Ser-Leu$. The number of codons that encode the amino acids present in this peptide is given below:Phe: $2$ codons...

Assume that a cell culture was started with five human fibroblast cells. Two cells did not divide even once whereas the other three cells completed three rounds of cell d...

Which of the following statements are $CORRECT$? Viruses can play a role in causing human cancer.A tumor suppressor gene can be turned off without any change in its $DNA$...

Determine the correctness or otherwise of the following Assertion [$a$] and the Reason [$r$] regarding mammalian cells.Assertion [$a$]: Cells use $Ca^{2+}$, and not $Na^{...

$DNA$ synthesized from an $RNA$ template is calledrecombinant $DNA$transcript$T-DNA$complementary $DNA$

During a positive-negative selection process, transformed animal cells expressing __________________ are killed in presence of ganciclovir in the medium.Pyruvate kinasevi...

A vector derived from which one of the following viruses is used for high - frequency genomic integration of a transgene in animal cells?AdenoviruAdeno-associated virusLe...

Which one of the following statements about $Agrobacterium \;Ti\; plasmid$ is $CORRECT$?$Vir$ genes are located within the $T-DNA$ segmentPhytohormone biosynthesis genes ...

Amino acid sequences of cytochrome $c$ and ribulose $5$-phosphate epimerase from $40$ organisms were chosen and phylogenetic trees were obtained for each of these two pro...

The Bt toxin gene from $Bacillus\; thuringiensis$ used to generate genetically modified crops is$cry$$cro$$cdc$$cre$

Tetracycline inhibits theinteraction between $tRNA$ and $mRNA$translocation of $mRNA$ through ribosomepeptidyl transferase activitybinding of amino-acyl $tRNA$ to ribosom...

Which one of the following enzymes is encoded by human immunodeficiency virus $(HIV)$ genome?Reverse transcriptasePhospholipasePhosphatase$ATP$ synthase

Which one of the following techniques can be used to compare the expression of a large number of genes in two biological samples in a single experiment?Polymerase chain r...

Which of the following processes can increase genetic diversity of bacteria in nature?ConjugationTransformationTransductionTransfection$P$ only$P$ and $Q$ only$P, Q$ and ...

A mutation in a gene that codes for a polypeptide results in a variant polypeptide that lacks the last three amino acids. What type of mutation is this?Synonymous mutatio...