Final answer:
Yeasts are excellent models for studying human cellular signaling due to the evolutionary conservation of signaling components such as G-protein coupled receptors, which allow the study of signaling cascades with greater simplicity and efficiency.
Step-by-step explanation:
Yeast is considered an excellent model for studying cellular signaling in humans due to several key characteristics. Specifically, yeasts are advantageous because they present conserved signaling components that are evolutionarily similar to those in human cells. For instance, signaling in yeast uses G-protein coupled receptors (GPCRs), much like insulin signaling in humans, suggesting a shared evolutionary pathway.
This evolutionary conservation is exemplified in the yeast mating factor response, where a signaling molecule called mating factor binds to cell-surface receptors, initiating a signaling cascade involving protein kinases and GTP-binding proteins resembling G-proteins. This makes yeasts a valuable model for learning more about human signaling pathways, which are often more complicated due to multicellular complexity.
Moreover, the fact that yeasts multiply quickly and have simpler life processes compared to multicellular organisms allows scientists to study signaling cascades with greater ease. This similarity yet simplicity helps in accurately modeling human signaling components and understanding their functions more than 100 words without the additional complexity found in multicellular organisms.