GATE Biotechnology Practice Quiz

Question 1

In a typical PCR amplification starting with a single double-stranded DNA molecule, assuming $100\%$ amplification efficiency and no plateau effect, how many double-stranded DNA molecules are expected after $10$ cycles?

Accepted Answer

$1024$

Question 2

Which one of the following enzymes is primarily responsible for relaxing positive supercoils ahead of the replication fork in bacterial DNA replication?

Accepted Answer

DNA gyrase

Question 3

A recombinant plasmid is constructed using a vector of size $3.0\,\text{kb}$ and an insert of size $1.5\,\text{kb}$. If this recombinant plasmid is completely digested with a restriction enzyme that cuts once within the vector and once within the insert, how many DNA fragments will be observed on an agarose gel?

Accepted Answer

Two fragments

Question 4

For an enzyme following Michaelis-Menten kinetics, the initial velocity is $v=60\,\mu\text{mol}\,\text{min}^{-1}$ at substrate concentration $[S]=2\,\text{mM}$. If $V_{\max}=100\,\mu\text{mol}\,\text{min}^{-1}$, what is the approximate value of $K_m$?

Accepted Answer

$1.33\,\text{mM}$

Question 5

In a continuous stirred tank bioreactor operating at steady state without cell recycle, the dilution rate is $D=0.25\,\text{h}^{-1}$. If the cell concentration in the reactor remains constant, what is the specific growth rate $\mu$ of the organism?

Accepted Answer

$0.25\,\text{h}^{-1}$

GATE Biotechnology

Practice Quizzes

GATE Biotechnology Practice Quiz

Michaelis Menten Enzyme Kinetics Fundamentals | GATE Biotechnology