Chapter 21 Part A&B - BLG 102 - The Lymphatic System and Lymphoid Organs and Tissues

These flashcards cover essential vocabulary related to the human immune system, focusing on innate and adaptive defenses.

Lymph Nodes

Act as lymph filters that cleanse the lymph by removing microorganisms and debris.

Macrophages

Large white blood cells that remove and destroy microorganisms and debris in the lymph.

Innate Defense System

The body's first and second lines of defense against pathogens, which are non-specific.

First Line of Defense

Includes external body membranes like skin and mucosae that act as physical barriers.

Second Line of Defense

Includes phagocytes, antimicrobial proteins, and inflammation that helps inhibit the spread of invaders.

Acid Mantle

Acidity of the skin and some mucous secretions that inhibits microbial growth.

Defensins

Antimicrobial peptides that inhibit microbial growth on skin and mucous membranes.

Phagocytosis

The process by which phagocytes recognize, engulf, and destroy pathogens.

Natural Killer Cells (NK Cells)

Large granular lymphocytes that can kill cancer and virus-infected cells before the adaptive immune system is activated.

Inflammation

A tissue response to injury that helps prevent spread of damaging agents and alerts the adaptive immune system.

Interferons (IFN)

Immune-modulating proteins secreted by infected cells to warn neighboring cells.

Complement System

A group of blood proteins that enhance the immune response by promoting inflammation and directly destroying bacteria.

Pyrogens

Substances secreted by leukocytes and macrophages that raise body temperature during a fever.