1. By :Allen S., David S. , Justin H. , Jenai N.,
The Immune System
By :Allen S., David S. , Justin H. , Jenai N.,

2. What are the major functions of the immune system?
Introduction
The immune system is the body’s defense against infectious diseases and organisms that would be harmful. With all of the cells and organs put together in the immune system, work together in order to protect the body.
When functioning in a proper manner, identifies and protects the body from harmful things such as parasites, viruses, and other harmful bacteria.
What are the major functions of the immune system?
The immune system is made up of of multiple cells, proteins, tissues, and organs that work together to defend the body from infected microorganisms that include bacteria, viruses and fungi. The immune system’s main goal is to fight off bad bacteria.

3. Functions of each part of the immune system.
Thymus – a gland in between a person’s lungs. It’s main function is to keep T – cell’s which are an important white blood cell thriving.
White Blood Cell- a colorless cell that circulates in the blood and body fluids and is involved in counteracting foreign substances and disease; a white (blood) cell. There are several types, all amoeboid cells with a nucleus, including lymphocytes, granulocytes, monocytes, and macrophages.
Antibodies-a blood protein produced in response to and counteracting a specific antigen. Antibodies combine chemically with substances that the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood
Epidermis-the outer layer of cells covering an organism, in particular.
Cilia-a short, microscopic, hairlike vibrating structure. Cilia occur in large numbers on the surface of certain cells, either causing currents in the surrounding fluid, or, in some protozoans and other small organisms, providing propulsion.
Mucus-a slimy substance, typically not miscible with water, secreted by mucous membranes and glands for lubrication, protection, etc.
Saliva-watery liquid secreted into the mouth by glands, providing lubrication for chewing and swallowing, and aiding digestion.

4. Describe each line of defense
The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.
The second line of defence is a resistance that destroys invaders in a general way without targeting certain individual destruction to one specific infection. Phagocytic cells ingest and destroy all microbes that pass through the body tissues. An inflammatory response follow that first process.
The third line of defense is a specific resistance. The system relies on antigens which are specific subatances that are found within foreign microbes. Antigens are mainly proteins that soon create an immune response after serving as a stimulus. Specialized cells of the immune system called hymphocytes are B - Cells and T - Cells.

5. Organs of the Immune System
In the immune system there are many different organs that make it up. These different organs have different functions to make the immune system work properly.
The bone marrow produces defense cells. The cells produced are differentiated within the thymus.
The thymus, which is only fully developed as a child, is slowly turned to fat tissue. This organ is placed behind the breast bone, and above the heart. This is also where defense cells are differentiated.
The spleen is located above the left abdomen beneath the diaphragm. This organ mainly produces defense cells and blood.
Tonsils also belong to the defense system and are located in the throat and palate. Being the organ’s position, the defense cells come in contact with pathogens earlier than other defense cells.

6. Interactions with other Body Systems
Every individual body system is able to work with a different kind of body system. The immune system is an example of body systems working together. The immune system carries many different defense cells with make sure that there are no infections and that the body is protected.
The immune system works closely with the circulatory system with transporting those defense cells throughout the body. The defense cells travel around the body trying to make sure to protect the body from infections.
The immune system also works with the digestive system, as it is critical to a proper working immune system. Places like the tonsils and the appendix are where the body figures out which substances are food and which are pathogens. This helps the immune system do its job normally and effectively.
In addition, the immune system works with the musculoskeletal system as the musculoskeletal system is where the muscles are moving throughout the body and also moving lymph. This shows why exercise and physical activity is critical to the immune system working.

7. Fun Facts about the Immune System
The immune system is a complex fighting system powered by five liters of blood and lymph. Lymph is a clear and colorless liquid that passes throughout the tissues of the body. Together, these two fluids transport all the elements of the immune system so they can do their jobs.
The defenses in the body die and regenerate everyday. The immune system, includes white blood cells produced in bone marrow that are called neutrophils. The cells must regenerate.
Sleep has a great amount of importance as the immune system requires enough sleep from the body in order to complete his job correctly.
Other parts of the immune system include the bone marrow, where white blood cells are produced; lymph nodes, which produce and store infection-fighting cells throughout the body.
The immune system is a complex fighting system powered by five liters of blood and lymph. Lymph is a clear and colorless liquid that passes throughout the tissues of the body. Together, these two fluids transport all the elements of the immune system so they can do their jobs.