The immune system is composed of organs, tissues, cells, and chemical messengers that interact to protect the body from external invaders and its own internally altered cells. The chemical messengers arecytokines which are secreted by cells of the immune system that direct immune cellular interactions. Lymphocytes (leukocytes that are categorized as either B cells or T cells) secrete lymphokines. Monocytes and macrophages secrete monokines. Interleukins are a type of cytokine that send messages among leukocytes to direct protective action. The best way to understand this system is through the body's various levels of defense. The goal of pathogens is to breach these levels to enter the body, reproduce, and subsequently exploit healthy tissue, causing harm. The immune system's task is to stop them.
Scientific journal is a periodical publication intended to further progress of science, usually by reporting novel research. There are thousands of scientific journals in publication, and many more have been published at various points in the past. Most journals are highly specialized, although some of the oldest journals publish articles and scientific papers across a wide range of scientific fields. Scientific journals contain articles that are peer reviewed, to ensure that articles meet the journal's standards of quality, and scientific validity. The publication of the results of research is an essential part of the scientific method. If they are describing experiments or calculations, they must supply enough details that an independent researcher could repeat the experiment or calculation to verify the results. Each such journal article becomes part of the permanent scientific record.
Last date updated on January, 2021