MHT CET 202624 AprilEvening Shift
- Exam
- MHT CET
- Year
- 2026
- Date
- 24 April
- Shift
- Evening Shift
- Subject
- Biology
- Chapter
- Molecular Basis of Inheritance
MHT CET 2026 · 24 April · Evening Shift · Biology · Molecular Basis of Inheritance
The transforming principle in Griffith's experiment was detected...
The transforming principle in Griffith's experiment was detected _______.
Options
- AWhen heat killed S-strain of S. pneumoniae were mixed up with the R-strain.
- BWhen the live S-strain of S. pneumoniae were mixed up with the R-stain.
- CWhen live R-strain of S. pneumoniae were mixed up with the S-strain.
- DWhen heat killed R-strain of S. pneumoniae were mixed up with the S-strain.
Correct answer
A. When heat killed S-strain of S. pneumoniae were mixed up with the R-strain.
Step-by-step solution
In Griffith's experiment, the transforming principle was detected when heat-killed S-strain (virulent) bacteria were mixed with live R-strain (non-virulent) bacteria and injected into mice.
The mice died of pneumonia, and live S-strain bacteria were recovered from their blood. This indicated that some 'transforming principle' from the heat-killed S-strain had transformed the live R-strain into the virulent S-strain.
Answer: When heat killed S-strain of S. pneumoniae were mixed up with the R-strain.
The mice died of pneumonia, and live S-strain bacteria were recovered from their blood. This indicated that some 'transforming principle' from the heat-killed S-strain had transformed the live R-strain into the virulent S-strain.
Answer: When heat killed S-strain of S. pneumoniae were mixed up with the R-strain.