31.3 Immune Responses

Data Table-

ruler

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31.3 Immune Responses

KEY CONCEPTThe immune system has many responses to pathogens and foreign cells.

31.3 Immune Responses

Two types of responses # 1 Nonspecific Responses-the same for every pathogen

A. Inflammation

B. blood vessels become leaky.

C. white blood cells movetoward infection anddamaged tissue

D. characterized by swelling, redness, and pain

capillary wallextracellular space

white blood cell

31.3 Immune Responses

• E. Fever-body temperature increases.

– High fevers can cause seizure, brain damage, and even death.

– Low fevers stimulate white blood cells to mature.

31.3 Immune Responses

2. Specific Responses

1st detect antigens (surface proteins on pathogens

Each pathogen has a different antigen.

virus

antigens

31.3 Immune Responses

pathogen

antigens

T cell

receptors activated T cells

antigens

memory T cells

• Two types of specific immune responses.

A. Cellular immunity uses T cells to destroy infected body cells.

31.3 Immune Responses

.

B. Humoral immunity uses B cells to produce antibodies.

memory B cells

activated B cells

antibodies

B cell

T cell

pathogen

31.3 Immune Responses

• Both responses produce memory cells.

– specialized T and B cells– provide acquired (active) immunity

B cellT cell

31.3 Immune Responses

The immune system rejects foreign tissues.

• Tissue rejection occurs in organ or tissue transplants.• Tissue rejection is the result of an immune response.

– immune system detects protein markers on the donor tissue

– makes antibodies against the donor’s tissue