When doing medical research with human subjects, which four limitations are unavoidable? A- It’s often impossible to repeat trials on the same subjects.
B- Subjects may report an inaccurate medical history.
C- It can be difficult to control all possible variables.
D- It’s impossible to come up with testable scientific questions for human subjects.
E- There are ethical or privacy concerns to consider.

One of the purposes of transcription is to produce a sequence of bases that

Q: a: in sexually reproducing animals, once fertilization of the egg takes place, the exists as a single cell until cell division begins

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.