Mometrix Immune System Flashcards

What is the function of the immune system?

To protect the body against invading pathogens including bacteria, viruses, fungi, and protists.

What major systems and structures are part of the immune system?

The lymphatic system, red bone marrow, and white blood cells (leukocytes).

Where are lymph nodes concentrated?

Neck, armpits, and groin areas

What does the thymus do?

It serves as a maturation chamber for immature T cells.

What does the spleen do?

It cleans the blood of dead cells and pathogens.

What are Peyer’s patches?

Immune structures in the small intestine that protect the digestive system from pathogens.

What are the three major categories of leukocytes?

Monocytes (macrophages, dendritic cells), granulocytes (neutrophils, basophils, eosinophils), and lymphocytes (T cells, B cells, NK cells).

What do macrophages do?

Phagocytose (engulf and destroy) pathogens and alert T cells.

What do dendritic cells do?

Present antigens to T cells.

What do neutrophils do?

Respond quickly to invaders; they are short-lived phagocytes.

What do eosinophils do?

Attack large, multicellular invaders like parasites.

What do basophils do?

Release histamine for inflammatory responses and allergic reactions

What are the four main types of T lymphocytes?

Helper T cells,

killer (cytotoxic) T cells,

suppressor T cells,

and memory T cells.

What do helper T cells do?

Help fight infections by producing antibodies and other chemicals.

What do killer T cells do?

Destroy infected cells and tumor cells.

What do suppressor T cells do?

Stop the immune response when the battle is over.

What do memory T cells do?

Remain in the blood to protect against future infections.

What do B lymphocytes do?

Produce antibodies and differentiate into plasma cells and memory cells.

What do plasma cells do?

Produce antibodies specific to pathogens or foreign substances.

What is an antigen?

A substance that stimulates the immune system.

What do antibodies do?

Bind to antigens on pathogens and mark them for destruction

What are the two main types of immunity?

Innate (born with) and adaptive (developed through exposure or immunization).

What is active immunity?

When the body makes its own antibodies in response to an infection or vaccine.

What is passive immunity?

When antibodies are received from another source (e.g., mother or injection).

What is the function of macrophages?

Macrophages are phagocytes that alert T cells to the presence of foreign substances and engulf pathogens.

What is the role of T lymphocytes (T cells)?

T lymphocytes directly attack infected body cells (especially infected by viruses or bacteria).

What is the function of B lymphocytes (B cells)?

B lymphocytes produce antibodies and target specific bacteria for destruction.