1. List the two lines of nonspecific defense mechanisms with examples of each.
• External defense, which includes the skin and mucous membranes in the body.
• Internal defense which includes phagocytic cells and antimicrobial proteins.
2. What is meant by specific defense?
Defense mechanisms are said to be specific because depending on which one they focus on one specific part of the body or a specific type of pathogen.
3. Give examples of “barrier defense.”
An example of a barrier defense is the largest organ on the human body, the skin. This organ provides both physical and chemical barrier against the environment.
4. What is the role of phagocytic leukocytes?
the role of phagocytic leukocytes is to engulf invading microorganisms that have gone through the external defense.
5. What is the role of the lymphatic system?
The lymphatic system collects fluid that is lost by the blood and returns it back to the circulatory system.
6. How does the lymphatic system aid in immunity?
It stores defensive phagocytic cells that defend against substances that enter the lymph nodes.
7. Outline the significant steps that occur during an inflammatory response?
The significant steps in the inflammatory response are the release chemical signals, capillaries dilate, increases temperature.
8. What is an antigen?
A foreign substance that enters the body and alters the defenses in the body.
9. Identify several differences between the lymphocyctes.
a. B Lymphocytes: produced in the bone marrow and are part of the humoral response.
b. T Lymphocytes: mature in the thymus gland and are part of the cell mediated response.
10. What is the role of MHC?
The role of MHC is to be a surface marker to indicate to the helper T-cells if it is a foreign invader or self.
11. What is the role of cytotoxic T cells and describe their mechanism of action?
Cytotoxic T-cells destroy infected body cells