Why does a virus stay in a person for life, such as hepatitis

Plz fast biotechnology is a growing field of applied biology. many crops such as corn have been engineered to be resistant to herbicides. therefore farmers can spray these chemicals to kill weeds growing near the crop without worries of killing the crop itself how does this type of biotechnology work? a. by changing the genetic make up of the crops. b. by causing the crops to kill the weeds. c. by changing the type of crops used. d. by changing the location of the crops.

Label the offspring chromosomes a1, a2, b1, or b2. circle any mutation chromosomes.

Half of the polar bears in a small population die. this population may experience changes due to gene flow mutation genetic drift natural selection