Download Immune System notes

Immune System notes
Immune System: protects our bodies from disease causing
agents (antigen). This is done by our cells, tissues and organs
working together.
The IMMUNE SYSTEM protects us from, these 5 primary
disease causing agents:
1. bacteria – single celled
2. microbes – microscopic organisms
3. viruses – get into cells and multiply
4. toxins – poisons, such as a venom
5. parasites – feed off of another organism
Antigen- any organism that invades our body, see 5 disease
causing agents above.
Skin- our first line of defense against invading germs.
Mucus in our nose, mouth & eyes act as a barrier to protect
body by trapping disease causing organisms.
Enzymes in your mouth & Tears in your eyes helps to
breakdown viruses and bacteria.
Lymphatic system- works with the immune system to protect the
body from disease causing organisms.
Lymph is a clear fluid that carries white blood cells which is
filtered through the lymph nodes.
White Blood Cells (leukocytes)- protects our body from disease
causing agents.
2 types:
 Lymphocytes- identifies any antigens
 B cells- produce antibodies (made in bone
marrow)
 T cells- these destroy and trigger phagocytes to
begin working (made by thymus)
 B cells latch on and T cells destroy the disease
causing agent
Vaccination (vaccine)- a dead or weakened form of a disease,
introduced into your body to help your body recognize, destroy
and build up immunity to this disease (ex: flu shot)
Allergy is a reaction by a person’s immune system against a
normally harmless disease.