Recent questions in General Biology

Consider the equation$V=\dfrac{aS}{b+S+\dfrac{S^2}{c}}$Given $a = 4$, $b = 1$ and $c = 9$, the positive value of $S$ at which $V$ is maximum, will be _________

An enzyme catalyzes a reaction bydecreasing the energy of the substrate.decreasing the activation energy of the reaction.decreasing product stability.increasing the activ...

Natural proteins are composed primarily of $20$ $\alpha$-amino acids. Which one of the following statements is true for any of these amino acids in a solution of pH $1.5$...

Which one of the following organisms is an indicator of fecal contamination?$\textit{Escherichia coli}$$\textit{Streptococcus lactis}$$\textit{Bacillus subtilis}$$\textit...

In a thin layer chromatography experiment using a silica gel plate, a compound showed migration of $12.5$ cm and the solvent front showed migration of $18$ cm. The $R_f$ ...

Which one of the following mechanisms is used by human pathogens to evade host immune responses?Somatic hypermutationAntibody productionAntigenic variationComplement acti...

If the nucleotide composition $(\%)$ of a viral genome is $A = 10$, $U = 20$, $C = 40$, and $G = 30$, which one of the following is this genome?Double stranded RNASingle ...

Which one of the following techniques can be used to determine the structure of a $15$ kDa globular protein at atomic resolution?Raman spectroscopyIR spectroscopyUV spect...

Assertion [a]: Gram negative bacteria show staining with saffranin.Reason [r]: Gram negative bacteria have an outer membrane with lipopolysaccharides.Both [a] and [r] are...

Enzyme-linked immunosorbent assay (ELISA) is used forquantifying antibody levels in blooddetermining the molecular weight of an antigenpurifying proteins from biological ...

Macrophages eliminate pathogenic bacteria upon activation byNK cellsbasophilsCD$4+$ T cellsplasma cells

If a protein contains four cysteine residues, the number of different ways they can simultaneously form two intra-molecular disulphide bonds is __________.

Secretory proteins synthesized by ER-associated ribosomes traverse throughmitochondriaperoxisomesthe Golgi apparatusthe nucleus

During protein synthesis, tRNAs are NOT involved incharginginitiationelongationtermination

In eukaryotes, cytokinesis is inhibited bycytochalasin Dvinblastinenocodazolecolchicine

A proto-oncogene is suspected to have undergone duplication in a certain type of cancer. Of the following techniques, which one would verify the gene duplication?Northern...

An enzymatic reaction exhibits Michaelis-Menten kinetics. For this reaction, on doubling the concentration of enzyme while maintaining $[S]>>[E_0]$both $K_m$ and $V_{\tex...

The transcription factor $X$ binds a $10$ base pair DNA stretch. In the DNA of an organism, $X$ was found to bind at $20$ distinct sites. An analysis of these $20$ bindin...

A bacterium has a genome of size $6$ million base pairs. If the average rate of DNA synthesis is $1000$ base pairs/second, the time taken (in minutes) for replication of ...

Which one of the following graphs represents the kinetics of protein precipitation by addition of ammonium sulphate? On the $Y$-axis, [Protein] represents the concentrati...

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...

The circular dichroism spectra of three proteins $P$, $Q$, and $R$ are given below:Choose the correct combination.$P: \alpha- \text{helix}, Q: \beta- \text{sheet}, \text{...

Which one of the following amino acids has three ionizable groups?GlycineLeucineValineLysine

The concentration (in micromolar) of NADH in a solution with $A_{340}=0.50$ is _________Given data: Path length $=1$ cm; Molar extinction coefficient of NADH $\varepsilon...

The specific activity of an enzyme in a crude extract of $\textit{E.coli}$ is $9.5$ units/mg of protein. The specific activity increased to $68$ units/mg of protein upon ...

An immunocompetent person becomes infected with a pathogenic strain of bacteria. Which one of the following graphs correctly depicts bacterial load in this person over ti...

The genome is diploid at the end of which phases of a human mitotic cell cycle?$\text{G2 & S}$$\text{G1 & M}$$\text{M & S}$$\text{G1 & G2}$

If the chemical composition of proteins in an organism is $CH_{1.5}O_{0.3}N_{0.3}S_{0.004}$, the mass percentage of carbon in the protein is __________Given data: Atomic ...

The interaction energy $E$ between two spherical particles is plotted as a function of the distance $(r)$ between them. When $r<a$, where $a$ is a constant, the net force...

A DNA strand of length $25$ nm wraps diametrically around the circumference of a spherical histone-octamer once. The radius (nm) of the histone-octamer is _______Given da...

One hunderd E.coli cells are each infected by a single $\lambda$ phage particle. The ratio of the number of phage particles committing to lysogeny to those committing to ...

Which of the following conditions promote the development of human autoimmune disorders?Inability to eliminate self-reactive lymphocytesGeneration of auto-antibodiesAbili...

Which one of the following complement proteins is the initiator of the membrane attack complex$C3a$$C3b$$C5a$$C5b$

Levinthal’s paradox is related toprotein secretionprotein degradationprotein foldingprotein trafficking

Based on the heavy chain, which one of the following antibodies has multiple subtypes?IgMIgDIgEIgG

The Cytokinetic organelle in plant cells iscentriolePhragmoplastproplastidchromoplastid

Anergy refers tonitochondrial dysfunctionallergy to environmental antigens unresponsiveness to antigensa state of no energy

ABO blood group antigens in humans are differentiated from each other on the basis ofsialic acidlipidsspectringlycoproteins

Which one of the following organisms is used for the determination of phenol coefficient of a disinfectant?Salmonella typhiEscherichia coliCandida albicansBacillus psychr...

A single subunit enzyme converts $420$ $\mu$moles of substrate to product in one minute. The activity of the enzyme is ________ $\times 10^{-6}$ Kalal.