What are innate and adaptive immune systems, how they work and how
they interact.
Adaptive immunity is the ability of the body to defend itself against specific invading agents
Antigens are substances recognized as foreign that provoke immune responses
Adaptive immunity has both specificity and memory and is divided into 2 types
1. Cell-mediated
2. Antibody-mediated
In cell-mediated immunity:
An antigen is recognized and bound
A small number of T cells proliferate and differentiate into a clone of effector cells
The antigen is eliminated
In antibody-mediated immunity:
An antigen is recognized and bound
Helper T cells costimulate the B cell so the B cell can proliferate and differentiate into a
clone of effector cells that produce antibodies
The antigen is eliminated
Innate immunity refers to a variety of body responses that serve to protect us against invasion of a wide
variety of pathogens and their toxins.
We are born with this kind of immunity
Two lines of defense: Nonspecific disease resistance fight a wide variety of invaders.
1st: Skin and mucous membranes: barriers, antimicrobial substances
2nd: Internal defenses (cellular defenses), inflammation, and fever
Describe the anatomy and functions of the spleen.
a. The spleen is the largest single mass of lymphatic tissue in the body.
It is found in the left hypochondriac region between stomach and the
diaphragm. It is composed of white pulp and red pulp. Red pulp filters
blood and gets rid of old or damaged blood cells. White pulp consists
of immune cells and helps fight infection. The spleen acts as a blood
filter, if it detects bad bacteria, viruses in the blood, it and the lymph
nodes create lymphocytes which act as defenders.