Sometimes the most practical way to do an experiment is not to perform it in an animal, but to look at cell responses in culture. Cells from mice, humans, and other mammals have been used to establish cell culture lines that have been very important for research. You are studying a novel water-soluble mouse hormone. You know cell culture can be a practical model to reveal protein function, so you apply the hormone to yeast cells, but nothing happens. What is a likely explanation for why nothing happened in your experiment

Yeast cells likely do not have receptors that bind to this specific water-soluble mouse hormone

Explanation:

Receptors are molecules capable of binding specific signaling molecules (i.e., ligands). For example, steroid receptors can only bind to specific steroid hormones (e.g. estrogen, progesterone). Plasma membrane receptors are protein receptors that bind to water-soluble ligands. These receptors are embedded in the cell plasma membrane and usually contain several transmembrane domains. Examples of cell membrane receptors include G protein-coupled receptors (GPCRs), enzyme-linked protein receptors and ion channel receptors.