Assertion : The mRNA attaches itself to the ribosome via its 3' end.

Reason : The mRNA has F-capsular nucleotide and bases of lagging sequence.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both the assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both the assertion and reason are false.

In RNA thymine is replaced by

• uracil

• adenine

• thiamine

• guanine

253.

Extranuclear genes occurs in

• plastids and are not inherited

• plasmid and are not inherited

• mitochondria and are inherited by female

• mitochondria and are inherited by male

Assertion : Watson and Crick provided experimental proof of semiconservative nature of DNA replication.

Reason : DNA polymerase binds nucleotides in replication.

• If both Assertion and Reason are true and Reason is the correct explantion of Assertion

• If both Assertion and Reason are true and Reason is not the correct explanation of Assertion

• If Assertion is true but Reason is false

• If Assertion is false but Reason is true.

Match the following and choose the correct combination from the options given.

Column I (Chemical compounds)	Column II (Example)
A. Nitrogen base	1. RNA
B. Nucleoside	2. Thymidylic acid
C. Nucleotide	3. Cytidine
D. Nucleic acid	4. Uracil

• A - 1; B - 2; C - 3; D - 4

• A - 1; B - 3; C - 2; D - 4

• A - 4; B - 3; C - 2; D - 1

• A - 4; B - 1; C - 2; D - 3

• A - 4; B - 1; C - 2; D - 3

In eukaryotic genes, coding sequences are called

• introns

• exons

• regulatory sequence

• repetitive DNA

• repetitive DNA

Which site of the tRNA pairs through hydrogen bonding with the triplet codes on mRNA?

• Codon

• 5' end of tRNA

• 3' end of tRNA

• Anticodon

• Anticodon

Find the wrongly matched pair

• Har Gobind Khorana - synthesized RNA molecules chemically

• George Gamow - codon is triplet's

• Meselson and Stahl - regulation of gene expression

• Alec Jeffreys - DNA finger printing

• Alec Jeffreys - DNA finger printing

In eukaryotes, RNA polymerase II transcribes

• hnRNA

• 18S rRNA

• 28S rRNA

• tRNA

• tRNA

Identify the wrong statement about DNA

• The length of DNA is defined as the number of base pairs present in it

• Cytosine is common to both DNA and RNA

• In a nucleotide, the nitrogenous base is linked to a phosphate group

• Thymine is chemically 5-methyl uracil

• Thymine is chemically 5-methyl uracil