Human body of different cavities, separated areas which house different organ systems. The brain and central nervous system reside in an area protected from the rest of the body by the blood brain barrier. The lungs sit in the pleural cavity. The intestines, liver, and spleen sit in the abdominal cavity Height, weight, shape and other body proportions vary individually and with age and sex. Body shape is influenced by the distribution of muscle and fat tissue. Human physiology is the study of how the human body functions. This includes the mechanical, physical, bioelectrical, and biochemical functions of humans in good health,
Society for the Psychological Study of Social Issues ways, including active engagement in the scientific study of human behavior in critical social situations, sharing the results of that research in scholarly settings, and providing relevant research findings to those engaged in developing public policy. SPSSI members are concerned with both U.S. and international issues, and SPSSI has been affiliated with the United Nations as a Non-Governmental Organization (NGO) since 1987. While SPSSI has focused primarily on U.S. policy in the past, its international membership is constantly growing and international issues have become a larger part of its work. SPSSI writes policy briefs, sponsors advocacy days, and trains its