Macrophages are an important part of the immune system. A macrophage released signaling molecules that bound to receptors on the macrophage’s surface. This interaction activated the microphage further and caused it to produce proteins that regulate immune responses. What type of cell communication was involved in the scenario? Explain your answer.

Even though the ostrich is a flightless bird, ostriches still possess wings that stretch approximately two meters across when fully extended. scientists speculate that when dinosaurs became extinct, some of the birds that lived during that time became land dwellers since they were able to consume the food that the dinosaurs once ate. over time, these species grew larger and heavier. eventually, the ostrich species became too big to fly. the wings found on ostriches are known as a. analogous structures. b. homologous structures. c. vestigial structures. d. symmetrical structures.