The combining of chromosomes from genetically different gametes occurs during .

Apopulation has 1000 individuals. over a period of 1 year, 500 newindividuals are born. which equation shows how to calculate the birthrate ofthis population? a. 500 - 1000 = 0.5b. 1000 x 0.5 = 500c. 1000 - 500 = 2d. 1000 + 500 = 1500

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of

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.