Question

When Griffith injected heat-killed infectious bacteria mixed with live harmless bacteria, he found that the mice died because

A. the heat-killed infectious bacteria were not actually dead.

B.the live harmless bacteria were transformed into infectious bacteria.

C. the heat-killed infectious bacteria were able to kill the mice on their own.

D. the live harmless bacteria were able to kill the mice on their own

Answer 1

When Griffith injected a mixture of live harmless bacteria and heat-killed infectious bacteria into mice, the mice died. The recovered bacteria from the dead mouse showed that the harmless bacteria had transformed into the pathogenic bacteria.

Step-by-step explanation:

In Griffith's experiments, he found that when he injected mice with a mixture of live harmless bacteria (R strain) and heat-killed infectious bacteria (S strain), the mice died. Upon isolating the bacteria from the dead mouse, only the S strain of bacteria was recovered. When this isolated S strain was injected into fresh mice, the mice died as well. From these results, Griffith concluded that something had passed from the heat-killed S strain to the live R strain, transforming the R strain into the pathogenic S strain.