# Recent questions tagged gate2017

1
An enzyme catalyzes a reaction by decreasing the energy of the substrate. decreasing the activation energy of the reaction. decreasing product stability. increasing the activation barrier of the reaction.
2
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 $1.5$? Only the amino group is ionized. Only the carboxylic acid group is ionized. Both amino and carboxylic acid groups are ionized. Both amino and carboxylic acid groups are neutral.
3
Which one of the following organisms is an indicator of fecal contamination? $\textit{Escherichia coli}$ $\textit{Streptococcus lactis}$ $\textit{Bacillus subtilis}$ $\textit{Lactobacillus acidophilus}$
4
The surface area (in $m^2$) of the largest sphere that can fit into a hollow cube with edges of length $1$ meter is ______ Given data: $\pi=3.14$
5
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 $R_f$ value for the compound is ______
6
$\underset{x \to 0}{\lim} \dfrac{\sin(x)}{x}$ is ________
7
Which one of the following mechanisms is used by human pathogens to evade host immune responses? Somatic hypermutation Antibody production Antigenic variation Complement activation
8
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 RNA Single stranded RNA Single stranded DNA Double stranded DNA
9
Which one of the following techniques can be used to determine the structure of a $15$ kDa globular protein at atomic resolution? Raman spectroscopy IR spectroscopy UV spectroscopy NMR spectroscopy
10
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 true and [r] is the correct reason for [a]. Both [a] and [r] are true but [r] is not the correct reason for [a]. Both [a] and [r] are false. [a] is true but [r] is false.
11
The plant hormone indole-$3$-acetic acid is derived from histidine tyrosine tryptophan proline
12
Enzyme-linked immunosorbent assay (ELISA) is used for quantifying antibody levels in blood determining the molecular weight of an antigen purifying proteins from biological ﬂuids determining the molecular weight of an antibody
13
Macrophages eliminate pathogenic bacteria upon activation by NK cells basophils CD$4+$ T cells plasma cells
14
If a protein contains four cysteine residues, the number of different ways they can simultaneously form two intra-molecular disulphide bonds is __________.
15
Secretory proteins synthesized by ER-associated ribosomes traverse through mitochondria peroxisomes the Golgi apparatus the nucleus
16
For $y=f(x)$, if $\dfrac{d^2y}{dx^2}=0$, $\dfrac{dy}{dx}=0$ at $x=0$, and $y=1$ at $x=1$, the value of $y$ at $x=2$ is __________
17
During protein synthesis, tRNAs are NOT involved in charging initiation elongation termination
18
In eukaryotes, cytokinesis is inhibited by cytochalasin D vinblastine nocodazole colchicine
19
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 blotting Southern blotting South western blotting Western blotting
20
A polymerase chain reaction (PCR) was set up with the following reagents: DNA template, Taq polymerase, buffer, dNTPs, and Mg$^{2+}$. Which one of the following is missing in the reaction mixture? Helicase Single-stranded binding proteins Primers Reverse transciptase
21
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 $V_{\text{max}}$ will remain the same $K_m$ will remain the same but $V_{\text{max}}$ will increase. $K_m$ will increase but $V_{\text{max}}$ will remain the same. both $K_m$ and $V_{\text{max}}$ increase.
22
A $5$ liter chemostat is fed fresh medium at $0.2$ liters/minute having a substrate concentration of $25$ grams/liter. At steady state, the outgoing stream has substrate concentration of $2.5$ grams/liter. The rate of consumption (grams/liter/minute) of the substrate in the reactor is __________
23
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 $20$ binding sites showed the following distribution: What is the consensus sequence for the binding site of $X$? $\textrm{NGTCNNNTNN}$ $\textrm{AGTCACNTGC}$ $\textrm{CACCTANCTG}$ $\textrm{ANNNACGNGC}$
24
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 the genome will be ________.
25
At the transcription start site of a gene, any of the four nucleotides can occur with equal probability $p$. The Shannon Entropy $S$, given by $S= – \Sigma_{i=1}^4 p_i \ln p_i$, for this start site is _________
26
Which one of the following graphs represents the kinetics of protein precipitation by addition of ammonium sulphate? On the $Y$-axis, [Protein] represents the concentration of free protein in solution
27
The distribution of marks scored by a large class in an exam can be represented as a normal distribution with mean $\mu$ and standard deviation $\sigma$. In a follow-up exam in the same class, everyone scored $5$ marks more than their respective score in the earlier exam. For this ... $\mu<\mu_2; \sigma>\sigma_2$ $\mu>\mu_2; \sigma<\sigma_2$ $\mu<\mu_2; \sigma=\sigma_2$
28
The angle (in degrees) between the vectors $\overrightarrow{x}= \hat{i}-\hat{j}+2 \hat{k}$ and $\overrightarrow{y} = 2 \hat{i} – \hat{j}-1.5 \hat{k}$ is _________
29
Match the proteins in $\textbf{Group I}$ with cellular processes in $\textbf{Group II}$ ... $\text{P-,2 Q-3, R-1, S-4}$ $\text{P-4, Q-3, R-1, S-2}$ $\text{P-2, Q-3, R-4, S-1}$
30
The circular dichroism spectra of three proteins $P$, $Q$, and $R$ are given below: Choose the correct combination. $P: \alpha- \text{helix}, Q: \beta- \text{sheet}, \text{ and } R: \text{Random coil}$ ... $P: \beta- \text{Random coil}, Q: \alpha- \text{helix}, \text{ and }R: \text{sheet}$
31
Match the organisms in $\text{Column I}$ with the characteristics in $\text{Column II}$ ... $\text{P-3, Q-2, R-4, S-1}$ $\text{P-2, Q-1, R-4, S-3}$ $\text{P-4, Q-1, R-2, S-3}$
32
Which one of the following amino acids has three ionizable groups? Glycine Leucine Valine Lysine
33
Consider an infinite number of cylinders. The first cylinder has a radius of $1$ meter and height of $1$ meter. The second one has a radius of $0.5$ meter and height of $0.5$ meter. Every subsequent cylinder has half the radius and half the radius and half ... preceding cylinder. The sum of the volumes (in cubic meters) of these infinite numbers of cylinder is __________. Given data: $\pi = 3.14$
34
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 $\varepsilon_{340}= 6220 M^{-1}cm^{-1}$
35
Which one of the following organisms is responsible for crown gall disease in plants? $\textit{Xanthomonas campestris}$ $\textit{Rhizobium etli}$ $\textit{Agrobacterium tume faciens}$ $\textit{Erwinia stewartii}$
36
The value of $c$ for which the following system of linear equations has an infinite number of solutions is ________ $\begin{bmatrix}1 & 2 \\ 1 & 2 \end{bmatrix} \begin{bmatrix} x \\ y \end{bmatrix} = \begin{bmatrix} c \\ 4 \end{bmatrix}$
37
Match the plant hormones in $\textbf{Column I}$ with functions in $\textbf{Column II}$ ... $\text{P-4, Q-2, R-3, S-1}$ $\text{P-3, Q-1, R-2, S-4}$ $\text{P-2, Q-1, R-4, S-3}$
For an $\textit{E.coli}$ culture in the exponential phase of growth, optical density (OD) at $540$ nm is $0.3$ at $2$ hours and $0.6$ at $4$ hours. Assuming that the measured OD is linearly proportional to the number of $\textit{E.coli}$ cells, the growth rate (per hour) for this culture is _________.
The genome is diploid at the end of which phases of a human mitotic cell cycle? $\text{G2 & S}$ $\text{G1 & M}$ $\text{M & S}$ $\text{G1 & G2}$