Question

A bacterial culture is provided methionine and cysteine that have been labeled with a radioactive isotope, 35S. The bacteria are then infected with a bacteriophage. What constituent of the bacteriophage progeny will contain the majority of the 35S label?:a. The bacteriophage genomeb. The capsid (bacteriophage protein coat)c. The envelope (bacteriophage membrane)d. The bacteriophage nuclear envelope

Answer 1

The correct answer is b. The capsid (bacteriophage protein coat)

Step-by-step explanation:

Sulfur is mainly present in amino acids like methionine and cysteine which helps in making protein and bacterial capsid is made up of proteins. So when a bacteria which is provided with methionine and cysteine that have been labeled with a radioactive isotope 35S is infected with a virus then the capsid of progeny virus will contain the majority of radioactive sulfur.

Radioactive sulfur can not be present in the bacteriophage genome because the nucleic acids do not contain sulfur. Therefore the right answer is b.