Which of the following body structure and physiology of bird are not important for the flight of birds 1.feathery and light wings
2.four chambered heart
3. Use of gill as a breathing organ
4. hallow body to reduce weight

Study the diagram of a cell. which structure is found only in plant cells and functions in the process of photosynthesis? w x y z

In the practice of science, this type of reasoning is used to develop explanations.

In an experiment examining the effects tai chi on arthritis pain, callahan (2010) selected a large sample of individuals with doctor-diagnosed arthritis. half of the participants immediately began a tai chi course and the other half (the control group) waited 8 weeks before beginning. at the end of 8 weeks, the individuals who had experienced tai chi had less arthritis pain that those who had not participated in the course.