To understand Castleman disease, it helps to know about the bodyâs lymph system. Lymphoid tissue, also known as lymphatic tissue, is the main part of the immune system. It is formed by different types of cells that work together to help the body fight infections.
Observation Systems International Program. Demography, the science of human population (or more specifically, the study of population structure. and processes), draws together research from a number of disciplines, including economics, sociology, geography, public health, and genetics. In addition to the environmental impacts of.
Population Growth | Back to Top. A population is a group of individuals of the same species living in the same geographic area. The study of factors that affect growth, stability, and decline of populations is population dynamics. All populations undergo three distinct phases of their life cycle: growth.