Scientists use this method to turn off genes that cause defects.

a: natural selection

b: gene manipulation

c: genetic engineering

d: cloning

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.

10. in which phase will crossing-over occur? a. mitosis b. metaphase ii c. prophase i d. meiosis ii

Many body systems work together for proper functioning of the body and to maintain internal homeostasis. the works to break down food eaten before exercising. the takes in the nutrients obtained from the food. the body sweats as a mechanism to cool off, because the is working to flush out toxins.