Joint movement occurs around an axis that is always to its plane.

perpendicular

Explanation: Joint can be found in areas of the body where two or more bones are connected together, practical examples in the human body can be traced to our elbow, wrist, hip, knee. At Each of these points mentioned, it could be observed that it serves as a meeting point for two or more bones which are linked and formed around an axis. This joints enables us to conveniently move, twist our rigid bones in different directions perpendicular to the plane (that is in a direction opposite or away from the direction of the plane).

answer; i believe that the correct answer is (lung);

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."