|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.
Journal Article is sometimes called a Scientific Article, a Peer-Reviewed Article, or a Scholarly Research Article. Together, journal articles in a particular field are often referred to as The Literature.
Journal articles are most often Primary Research Articles. However, they can also be Review Articles. These types of articles have different aims and requirements. Sometimes, an article describes a new tool or method.
Because articles in scientific journals are specific, meticulously cited and peer-reviewed, journal databases are the best place to look for information on previous research on your species. Without a background in the field, journal articles may be hard to understand - however, you do not need to understand an entire article to be able to get valuable information from it.