Final answer:
Acetabularia was a good model organism for locating genetic material due to its large unicellular structure and clear differentiation, allowing for easy observation and manipulation in Hämmerling's experiments, which showed the nucleus as the source of genetic information.
Step-by-step explanation:
The alga Acetabularia was a good model organism for Joachim Hämmerling to use to identify the location of genetic material because it is a large, unicellular organism with a clear differentiation of parts, making it easy to manipulate and observe. Its single cell can grow up to several centimeters and consists of a foot containing the nucleus, a stalk, and a cap. Hämmerling's experiments demonstrated that when the cap was removed, it could regenerate; however, if the foot containing the nucleus was removed, regeneration did not occur. This provided strong evidence that the nucleus housed the genetic information necessary for cell regeneration. Furthermore, Hämmerling conducted graft experiments between different species of the alga with distinct cap morphologies and observed that the properties of the regenerated caps were determined by the species of the foot containing the nucleus, further solidifying the nucleus as the location of genetic material.