C3.2 疾病的防禦（生物體）：练习题

Which component of the blood clotting cascade is responsible for converting the soluble protein fibrinogen into the insoluble protein fibrin?

How do vaccines provide immunity against specific pathogens without causing the disease itself?

Autoimmune diseases occur when the immune system mistakenly attacks the body's own tissues. Which of the following is a plausible underlying mechanism for the development of an autoimmune disease?

Which of the following describes the primary role of mucous membranes in the body's non-specific defense system?

Why are antibiotics ineffective against viral infections such as the common cold or influenza?

State the role of platelets in the early stages of the blood clotting process.

Explain the role of memory cells in providing long-term immunity after primary exposure to a pathogen.

Describe the mechanism by which Human Immunodeficiency Virus (HIV) infection leads to the development of AIDS.

The human body possesses several primary defense mechanisms to prevent the entry of pathogens into the internal environment.
a) Describe how the skin acts as both a physical and chemical barrier against infection.
b) Explain the role of mucous membranes in protecting areas of the body that are not covered by skin, such as the respiratory tract.

a) Explain the difference between a primary and a secondary immune response when a human is exposed to a specific pathogen for the first time and then a second time.
b) Outline the roles of plasma cells and memory cells in these responses.