Cell Type Dichotomous Key 1a cell has a nucleus and organelles → go to # 2 1b cell has no nucleus or organelles → bacterial cell 2a cell has a cell wall → go to # 3 2b cell has no cell wall → animal cell 3a cell has chloroplasts → plant cell 3b cell has no chloroplasts → fungal cell What type of cell is A? A)animal B)bacterial C)fungal D)plant

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.