Recent questions tagged molecular-biology

Messenger $\text{RNAs (mRNAs)}$ translate to generate polypeptides and the translation terminates at the $\text{UGA, UAG}$ or $\text{UAA}$ stop codons. The $\text{AGA}$ c...

The RNA sequence below depicts the part of a $330$ nucleotides long $\text{mRNA}$ and it encodes the $\text{C}$-terminal portion of a protein.$5^{\prime}-\ldots \ldots$ $...

​​​​Which of the following enzymes is/are involved in the biogenesis of miRNA?DroshaCas$9$XRCC$4$Dicer

​​​​Which of the following statements about initiation of DNA replication in eukaryotes is/are true?DNA replication is initiated at the origin of replication licensed by ...

​​​​Which of the following statements is/are true about telomerase?Telomerase has $5^{\prime}-3^{\prime}$ DNA-dependent DNA polymerisation activityTelomerase has $5^{\pri...

​​​​Which of the following methods is/are used for identifying histone modifications?ChIP-seqMass spectrometryImmunofluorescencePatch-clamp electrophysiology

Match the enzyme (Column I) with its corresponding function (Column II).\begin{array}{|c|c|c|}\hline & \text{Column I} & \text{Column II} \\\hline & \text{P. Primase} & 1...

Which of the following conditions induce(s) the expression of $\beta$-galactosidase gene in the lac operon?Absence of glucoseAbsence of lactosePresence of glucosePresence...

Determine the correctness or otherwise of the following Assertion $[\text{a}]$ and the Reason $[\mathrm{r}]$.Assertion $[\mathrm{a}]$: In multicellular organisms, cells o...

Which of the following methods are used for detection of DNA and RNA, respectively?Southern and Northern blotting Southern and Western blottingNorthern and Southern blott...

Match the types of RNA in Group I with their corresponding function in Group II.Group IGroup IIP. mRNA1. Serves as adaptors between mRNA and amino acids during protein sy...

Match the virus in Group I with the type of genome it contains in Group II.Group IGroup IIP. T4 bacteriophage1. dsRNAQ. SARS-CoV-22. ssDNAR. Pseudomonas phage $\phi 6$3. ...

The event(s) that lead(s) to inactivation of tumor suppressor genes in cancer cells is(are)gene amplificationpromoter methylationloss of heterozygosityhistone acetylation

Methylation of $\mathrm{CpG}$ islands near the promoter of a gene can inhibit transcription bypreventing RNA polymerase bindingfacilitating repressor bindingfacilitating ...

Which of the following statement(s) is(are) TRUE about induced pluripotent stem cells?They can self-renewThey require specific signals to maintain their stemnessThey cann...

Which of the following are CORRECT about protein structure?Secondary structure is formed by a repeating pattern of interactions among the polypeptide backbone atomsTertia...

Adenine can undergo a spontaneous change to hypoxanthine in a cell, leading to a $\text{DNA}$ base pair mismatch. The $\text{CORRECT}$ combination of enzymes that are inv...

Which of the following statement(s) is(are) CORRECT regarding the $lac$ operon in $E. coli$ when grown in the presence of glucose and lactose?At low glucose level, the op...

Which one of the following techniques/tools is $\text{NOT}$ used for inserting a foreign gene into a cell?$\text{DNA}$ microarrayElectroporationGene gunMicroinjection

The cellular process which utilizes $\text{RNA}$-induced silencing complex to block gene expression is$\text{RNA}$ editing$\text{RNA}$ interference$\text{RNA}$ polyadenyl...

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 $DNA$ sequence shown below is to be amplified by $PCR$:$5{}'$ GCTAAGATCTGAATTTTCC$\dots\dots$TTGGGCAATAATGTAGCGC$3{}'$$3{}'$ CGATTCTAGACTTAAAAGG$\dots\dots$AACCCGTTAT...

Carl Woese used the gene sequence of which one of the following for phylogenetic taxonomy of prokaryotes?A ribosomal $RNA$ of large ribosomal subunitA ribosomal $RNA$ of...

Determine the correctness or otherwise of the following Assertion [$a$] and the Reason [$r$].Assertion [$a$]: Dam methylase protects $E$. coli $DNA$ from phage endonuclea...

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...

Match sub-cellular organelles listed in $Group\; I$ with their features listed in $Group\; II$:$$\begin{array}{|cl|cI|cI|cI|cI|c|}\hline&\textbf{Group I} & \textbf{Group ...

Protein $P$ becomes functional upon phosphorylation of a serine residue. Replacing this serine with _____________ will result in a phosphomimic mutant of $P$.alanineaspar...

Ras protein is atrimeric GTPase involved in relaying signal from cell surface to nucleusmonomeric GTPase involved in relaying signal from cell surface to nucleustrimeric ...

Which of the following are energy transducing membranes?Plasma membrane of bacteriaInner membrane of chloroplastsInner membrane of mitochondria$P$ and $Q$ only$P$ and $R$...

$DNA$ synthesis in eukaryotes occurs during which phase of the mitotic cell cycle?$M$$G_{1}$$S$$G_{10}$

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...

What will be the binding status of regulatory proteins in lac operon when concentrations of both lactose and glucose are very low in the culture medium?Only the repressor...

ATP biosynthesis takes place utilizing the $H^+$ gradient in mitochondria and chloroplasts. Identify the correct sites of $H^+$ gradient formation.Across the outer membra...

Based on their function, find the ODD one out.miRNAsiRNAshRNAsnRNA

Match the proteins in $\textbf{Group I}$ with cellular processes in $\textbf{Group II}$$\begin{array}{|l|l|l|l|} \hline & \textbf{Group I} & & \text{Group II} \\ \hline P...

In DNA sequencing reactions using the chain termination method, the ratio of ddNTPs to dNTPs should be$0$$< 1$$1$$>1$

Choose the appropriate pair of primers to amplify the following DNA fragment by the polymerase chain reaction (PCR).$$\textrm{5’ – GACCTGTGG- – – – – – – – – – – – – – – ...

Match the compounds in $\text{Group I}$ with the correct entries in $\text{Group II}$.$\begin{array}{|l|l|l|l|}\hline & \textbf{Group I} & & \textbf{Group II} \\ \hline ...

Assuming random distribution of nucleotides, the average number of fragments generated upon digestion of a circular DNA of size $4.3 \times 10^5$ bp with $\textit{Alu}I (...

The 4-amino or 4-keto group of pyrimidine bases is located in themajor groove of the double stranded DNAminor groove of the double stranded DNAminor groove of the B form ...