However, contrary to what one is apt to read in anti-evolutionary literature, there is currently no evidence demonstrating that the appendix, as a separate organ, has a specific immune function in humans ( Judge and Lichtenstein 2001 ; Dasso et al. 2000 ; Williams and Myers 1994 , pp. 5, 26-29). To date, all experimental studies of the function of an appendix (other than routine human appendectomies) have been exclusively in rabbits and, to a lesser extent, rodents. Currently it is unclear whether the lymphoid tissue in the human appendix performs any specialized function apart from the much larger amount of lymphatic tissue already distributed throughout the gut. Most importantly with regard to vestigiality, there is no evidence from any mammal suggesting that the hominoid vermiform appendix performs functions above and beyond those of the lymphoid-rich caeca of other primates and mammals that lack distinct appendixes.
Liver disease can be prevented by following the right lifestyle and diet. Vaccinations that protect from Hepatitis A and Hepatitis B are widely available. Weight control, giving up smoking and alcohol, exercising regularly and a well-balanced diet will reduces the chances of developing a liver disease. Awareness about liver diseases must be increased. The causes and the complications of a liver disease need to be highlighted. The medications that lead to a liver disease also need to be stopped or their intake must be controlled and minimal. For instance, an overdose of acetaminophen or Tylenol will invariably cause a liver failure. Therefore one must never indulge in self medication.
Gonads start developing as a common primordium (an organ in the earliest stage of development), in the form of gonadal ridges ,  and only later are differentiated to male or female sex organs . The presence of the SRY gene ,  located on the Y chromosome and encoding the testis determining factor , determines male sexual differentiation. In the absence of the SRY gene from the Y chromosome, the female sex (ovaries instead of testes) will develop. The development of the gonads is a part of the development of the urinary and reproductive organs .