Question

Match column I with column II, and choose the correct combination from the options given below.

	Column I		Column II
a.	Monocistronic gene	1.	Prokaryotes
b.	Polycistronic gene	2.	Eukaryotes
c.	Exons	3.	Coding sequences
e.	Introns	4.	Intervening sequences

• A.
  $\begin{array}{cccc}\text{a}& \text{b}& \text{c}& \text{d}\\ 2& 1& 3& 4\end{array}$
  
• B.
  $\begin{array}{cccc}\text{a}& \text{b}& \text{c}& \text{d}\\ 1& 2& 3& 4\end{array}$
  
• C.
  $\begin{array}{cccc}\text{a}& \text{b}& \text{c}& \text{d}\\ 2& 1& 4& 3\end{array}$
  
• D.
  $\begin{array}{cccc}\text{a}& \text{b}& \text{c}& \text{d}\\ 1& 2& 4& 3\end{array}$
  

Answer 1

The correct option is A

$\begin{array}{cccc}\text{a}& \text{b}& \text{c}& \text{d}\\ 2& 1& 3& 4\end{array}$

Monocistronic gene - Eukaryotes
Monocistronic genes are those genes that transcribe mRNA which codes for only one polypeptide. These genes are found in eukaryotes.

Polycistronic gene - Prokaryotes
Polycistronic genes are those that transcribe mRNA which code for more than one type of polypeptide chain. These are found only in prokaryotes.

Exons - Coding sequence
Cistron is a part of a gene that codes for a polypeptide. In eukaryotic cells it is made up of coding sequences known as exons and non-coding segments known as introns.

Introns - Intervening sequences
Introns are non-coding sequences that intervene with the exons in a cistron and hence are called intervening sequences.