What anatomical feature of the veins maintains a unidirectional flow of blood back toward the heart?

Apatient has an open displaced fracture of the second cervical vertebra. this is her fifth visit and the fracture is healing normally. what icd-10-cm code is reported?

What are characteristics of minerals? select 3 choices

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.