- Reverse transcriptase has both ribonuclease and polymerase activities. Ribonuclease activity is required for
(1)the synthesis of new RNA strand
(2)the degradation RNA strand
(3)the synthesis of new DNA strand
(4)the degradation of DNA strand
Overview of Reverse Transcriptase Activities
Reverse transcriptase (RT) is a multifunctional enzyme essential for converting single-stranded RNA genomes of retroviruses into double-stranded DNA. RT possesses two main enzymatic activities:
-
Polymerase activity: Synthesizes DNA using RNA or DNA as a template.
-
Ribonuclease H (RNase H) activity: Specifically degrades the RNA strand of RNA/DNA hybrids formed during reverse transcription.
Function of RNase H Activity
-
The RNase H domain of reverse transcriptase cleaves the RNA strand in RNA/DNA hybrids.
-
This degradation is crucial because the newly synthesized DNA strand remains hybridized to the RNA template. Removal of the RNA strand allows subsequent synthesis of the complementary DNA strand to form double-stranded DNA.
-
RNase H activity also removes RNA primers (such as tRNA primers) used to initiate DNA synthesis.
Why RNase H Activity Is Required for RNA Strand Degradation
-
During reverse transcription, the RNA genome serves as a template for DNA synthesis.
-
The RNA strand must be removed to allow the formation of a complete double-stranded DNA molecule.
-
RNase H cleaves the RNA in the RNA/DNA hybrid, leaving the DNA free to serve as a template for the second DNA strand synthesis.
Explanation of the Options
-
The synthesis of new RNA strand
-
Incorrect. RNase H does not synthesize RNA; it degrades RNA.
-
-
The degradation of RNA strand
-
Correct. RNase H activity is responsible for degrading the RNA strand in RNA/DNA hybrids.
-
-
The synthesis of new DNA strand
-
Incorrect. DNA synthesis is carried out by the polymerase activity, not RNase H.
-
-
The degradation of DNA strand
-
Incorrect. RNase H specifically targets RNA strands, not DNA strands.
-
Summary Table
| Activity | Role of RNase H Activity |
|---|---|
| Synthesis of new RNA strand | Not performed by RNase H |
| Degradation of RNA strand | RNase H cleaves RNA in RNA/DNA hybrids |
| Synthesis of new DNA strand | Performed by polymerase domain, not RNase H |
| Degradation of DNA strand | RNase H does not degrade DNA |
Conclusion
The ribonuclease (RNase H) activity of reverse transcriptase is essential for degrading the RNA strand in RNA/DNA hybrids formed during reverse transcription. This degradation allows the synthesis of the complementary DNA strand and completion of double-stranded DNA formation. Therefore, the correct function of RNase H is the degradation of the RNA strand.
Keywords
reverse transcriptase, RNase H activity, ribonuclease H, RNA degradation, RNA/DNA hybrid, retroviral replication, DNA synthesis, polymerase activity, HIV reverse transcriptase, RNA strand removal
Final answer:
(2) the degradation RNA strand
41 Comments
Priti khandal
July 27, 2025Done sir
Priya dhakad
July 29, 2025The correct answer is 2 RNase H activity is responsible for degrading the RNA strand
Surbhi Rajawat
July 29, 2025The answer is 2nd because the ribonuclease activity for reverse transcriptase is essential to ensure the formation of complete ds DNA
Priya dhakad
July 29, 2025The correct answer is 2 RNase H activity is responsible for degrading the RNA strand
Soniya Shekhawat
July 29, 2025Easy sir
Anisha jakhar
July 29, 2025Correct option is 2. Degradation of RNA strand.
Pratibha
July 29, 2025Correct option is option (2)
RT is a multifunctional enzyme which formed the DNA from RNA template
RT has two main activities:-
1.polymerase activity – which synthesize DNA using RNA /DNA as a template
2.Riboneuclease H activity -which degrades the RNA strand of RNA/DNA hybrids formed during RT
Kajal
July 29, 2025Option 2 is right
Because Ribonuclease H is known to remove the rna strand
anurag giri
July 29, 2025Ans 2 Ribonuclease (RNase H) activity Specifically degrades the RNA strand of rna dna hybrids formed during reverse transcription.
Vijay kumar meena
July 29, 20252 correct because RNase degrading tha Rna strand
shruti sharma
July 29, 2025rnhase activity -degrade the rna
Dipti Sharma
July 29, 2025Correct answer: 2
Bcz Rnase H activity is responsible for degradation of RNA strand
Santosh saini
July 29, 2025Yes the correct option is 2 because RNase H is responsible for degrading RNA strand
Mohini
July 30, 2025Option 2 is the correct answer. Ribonuclease activity of RT is responsible for the degradation of RNA to separate RNA from the DNA strand.
Payal Gaur
July 30, 2025Ribonuclease (RNase H) responsible for degradation of RNA strand
Deepshikha choudhary
July 30, 2025Ribonuclease activity is responsible for degradation of RNA strands
Juber Khan
July 30, 2025Option (2) right bcz Rnase H doesn’t degrade dna and synthesis of new strand of dna /rna perform by poly.domain not Rnase H ….Rnase cleaves Rna in Rna /Dna hybrid
Santosh Saini
July 30, 2025Option 2 is the correct , RNase H degrade the RNA in the RNA/DNA hybrid for the free DNA
HIMANI FAUJDAR
July 30, 2025Answer is 2 , RnaseH involved in the degradation of RNA
Shivani panwar
July 30, 2025Ans is 2
Sir .. 😊
Asha gurzzar
July 30, 2025Ribonuclease will degrade the rna strand,as nucleases are enzymes used for degradation
Mansukh Kapoor
July 30, 2025The correct answer is option 2nd because ribonuclease activity is required for the degradation of the RNA rather than the DNA
Niti tanwar
July 30, 2025Answer is 2 bcz ribonuclease rnase H degradation of RNA
Mahima sharma
July 30, 2025Degradation of rna
Khushi Agarwal
July 31, 2025Correct answer is 2 degradation of rna strand
Khushi Vaishnav
July 31, 2025Reverse transcriptase is essential for degrading the RNA strand
Alec Joseph
July 31, 2025correct ans. is 2 because ribonuclease activity is responsible for degradation of the rna strand not for Dna strand.
Vanshika Sharma
July 31, 2025Opt is 2 ribonuclease activity is required for degradation of RNA strand
Dharmpal Swami
August 1, 2025Degradation of rna strand
SHOBHA SHARMA
August 1, 2025Degradation of rna strand
Shivani
August 1, 2025Rnase H activity is responsible for degradation of RNA so option 2 is correct
Deepika sheoran
August 2, 2025Degradation of rna strand.
Varsha tatla
August 2, 2025The ribonuclease activity of reverse transcriptase is required for degradation of rna in rna dna hybrid
Varsha tatla
August 2, 2025Ribonuclease activity of reverse transcriptase is required for degradation of rna in rna dna hybrid
Mahima Sharma
August 3, 2025Synthesis of new rna stand
Manisha choudhary
August 3, 2025Reverse transcriptase enzyme ki ribonucleases activity RNase-H domain RNA – DNA hybrid p RNA ko degrade krta h ribonucleotide k bich bond break krta h
Reverse transcriptase enzyme ki polymerization activity RNA s double strand DNA kaa formation krti h
Deepika sheoran
August 8, 2025Degradation of Rna strand
Aafreen Khan
August 23, 2025The degradation RNA strand bcoz RNase H activity cleavage RNA strand for formation of complete double strand DNA
vishal saini
September 18, 2025done sir 💯 this question is very easy
Komal Sharma
October 3, 2025The ribonuclease (RNase H) activity of reverse transcriptase is essential for degrading the RNA strand in RNA/DNA hybrids formed during reverse transcription. This degradation allows the synthesis of the complementary DNA strand and completion of double-stranded DNA formation. Therefore, the correct function of RNase H is the degradation of the RNA strand.
Deepika Sheoran
November 7, 2025Degradation of RNA strand.