What characteristics make yeasts a good model for learning about signaling in humans?

Yeasts is the process in which the unicellular organisms are developed by the multi-cellular characteristics by the string forming in the cells of the budding.

Cell signalling is the characteristics of the good model which are formed by the communication cells by which the actions of the cells are organised and the cells activities are maintained. And the signalling of the cell are produced by the chemical signals in the form of the ligands.