Aim: How does our immune system protect against antigens of pathogenic organisms?

HW 22

Read Ch 40 pages 1028 – 1048

Pg 1034 vocabulary

Pg 1050 Thinking visually

copy and complete concept map.

The human immune system is made up of…

• Lymphatic vessels• lymph nodes• lymphoid tissue

– bone marrow, thymus, tonsils, adenoids, Peyer's patches, and the appendix

and cells…

Cellular barriers to infection

• Neutrophils – Polymorphonuclear cells are recruited to the site of infection where they phagocytose invading organisms and kill them intracellularly

Cellular barriers to infection

• Macrophages – Tissue macrophages function in phagocytosis and intracellular killing of microorganisms.

Cellular barriers to infection

• Eosinophils

have proteins in granules that are effective in killing certain parasites

How do Lymphocytes Produce Antibodies?

Antibodies are..

Molecules in the blood or secretory fluids that tag, destroy, or neutralize bacteria, viruses, or other harmful toxins

Antibodies are chemicals that have antigen binding sites

Antigens are proteins on the foreign body (pathogens).

AntibodyAntigen

Antigen-binding sites

Bacteria With Antigens on Surface

Macrophage

T cell

B cell

Active B cells

T cell

Section 40-2

Humoral immunity is the body’s immune response

Plasma cell

Bacteria With Antigens on Surface

Macrophage

T cell

B cell

phagocyte called a macrophage engulfs a bacterium

Active B cells proliferate to produce clones of memory cells

T cell, activated by macrophage, becomes a helper T cell

Antigens are displayed on surface of macrophage after digestion of bacterium

T cell binds to activated macrophage

Section 40-2  Humoral ImmunityBacterial antigens also stimulate B cells

Plasma cell produces large amounts of antibody proteins, released intothe bloodstream

Work in the group

• Discuss why you get chicken pox once during childhood